If in .net ( I'm not sure if it works for all windows services)

• Stop the service (THis may be why you're having a problem.)
• InstallUtil -u [name of executable]
• Installutil -i [name of executable]
• Start the service again...

Unless I'm changing the service's public interface, I often deploy upgraded versions of my services without even unistalling/reinstalling... ALl I do is stop the service, replace the files and restart the service again...

wt = tt - cpu tm.
Tt = cpu tm + wt.

Where wt is a waiting time and tt is turnaround time. Cpu time is also called burst time.

It's much easier (and faster) to get this information by only parsing the output of ver:

@echo off
setlocal
for /f "tokens=4-5 delims=. " %%i in ('ver') do set VERSION=%%i.%%j
if "%version%" == "10.0" echo Windows 10
if "%version%" == "6.3" echo Windows 8.1
if "%version%" == "6.2" echo Windows 8.
if "%version%" == "6.1" echo Windows 7.
if "%version%" == "6.0" echo Windows Vista.
rem etc etc
endlocal

This table on MSDN documents which version number corresponds to which Windows product version (this is where you get the 6.1 means Windows 7 information from).

The only drawback of this technique is that it cannot distinguish between the equivalent server and consumer versions of Windows.

Under Linux you can create directory in one line:

import os
os.system("mkdir -p {0}".format('mydir'))

Runnable examples

Let's create and run some minuscule bare metal hello world programs that run without an OS on:

• an x86 Lenovo Thinkpad T430 laptop with UEFI BIOS 1.16 firmware
• an ARM-based Raspberry Pi 3

We will also try them out on the QEMU emulator as much as possible, as that is safer and more convenient for development. The QEMU tests have been on an Ubuntu 18.04 host with the pre-packaged QEMU 2.11.1.

The code of all x86 examples below and more is present on this GitHub repo.

How to run the examples on x86 real hardware

Remember that running examples on real hardware can be dangerous, e.g. you could wipe your disk or brick the hardware by mistake: only do this on old machines that don't contain critical data! Or even better, use cheap semi-disposable devboards such as the Raspberry Pi, see the ARM example below.

For a typical x86 laptop, you have to do something like:

1. Burn the image to an USB stick (will destroy your data!):

   sudo dd if=main.img of=/dev/sdX
   

2. plug the USB on a computer

3. turn it on

4. tell it to boot from the USB.

   This means making the firmware pick USB before hard disk.

   If that is not the default behavior of your machine, keep hitting Enter, F12, ESC or other such weird keys after power-on until you get a boot menu where you can select to boot from the USB.

   It is often possible to configure the search order in those menus.

For example, on my T430 I see the following.

After turning on, this is when I have to press Enter to enter the boot menu:

Then, here I have to press F12 to select the USB as the boot device:

From there, I can select the USB as the boot device like this:

Alternatively, to change the boot order and choose the USB to have higher precedence so I don't have to manually select it every time, I would hit F1 on the "Startup Interrupt Menu" screen, and then navigate to:

Boot sector

On x86, the simplest and lowest level thing you can do is to create a Master Boot Sector (MBR), which is a type of boot sector, and then install it to a disk.

Here we create one with a single printf call:

printf '\364%509s\125\252' > main.img
sudo apt-get install qemu-system-x86
qemu-system-x86_64 -hda main.img

Outcome:

Note that even without doing anything, a few characters are already printed on the screen. Those are printed by the firmware, and serve to identify the system.

And on the T430 we just get a blank screen with a blinking cursor:

main.img contains the following:

• \364 in octal == 0xf4 in hex: the encoding for a hlt instruction, which tells the CPU to stop working.

  Therefore our program will not do anything: only start and stop.

  We use octal because \x hex numbers are not specified by POSIX.

  We could obtain this encoding easily with:

  echo hlt > a.S
  as -o a.o a.S
  objdump -S a.o
  

  which outputs:

  a.o:     file format elf64-x86-64
  
  
  Disassembly of section .text:
  
  0000000000000000 <.text>:
     0:   f4                      hlt
  

  but it is also documented in the Intel manual of course.

• %509s produce 509 spaces. Needed to fill in the file until byte 510.

• \125\252 in octal == 0x55 followed by 0xaa.

  These are 2 required magic bytes which must be bytes 511 and 512.

  The BIOS goes through all our disks looking for bootable ones, and it only considers bootable those that have those two magic bytes.

  If not present, the hardware will not treat this as a bootable disk.

If you are not a printf master, you can confirm the contents of main.img with:

hd main.img

which shows the expected:

00000000  f4 20 20 20 20 20 20 20  20 20 20 20 20 20 20 20  |.               |
00000010  20 20 20 20 20 20 20 20  20 20 20 20 20 20 20 20  |                |
*
000001f0  20 20 20 20 20 20 20 20  20 20 20 20 20 20 55 aa  |              U.|
00000200

where 20 is a space in ASCII.

The BIOS firmware reads those 512 bytes from the disk, puts them into memory, and sets the PC to the first byte to start executing them.

Hello world boot sector

Now that we have made a minimal program, let's move to a hello world.

The obvious question is: how to do IO? A few options:

• ask the firmware, e.g. BIOS or UEFI, to do it for us

• VGA: special memory region that gets printed to the screen if written to. Can be used in Protected Mode.

• write a driver and talk directly to the display hardware. This is the "proper" way to do it: more powerful, but more complex.

• serial port. This is a very simple standardized protocol that sends and receives characters from a host terminal.

  On desktops, it looks like this:

  

  Source.

  It is unfortunately not exposed on most modern laptops, but is the common way to go for development boards, see the ARM examples below.

  This is really a shame, since such interfaces are really useful to debug the Linux kernel for example.

• use debug features of chips. ARM calls theirs semihosting for example. On real hardware, it requires some extra hardware and software support, but on emulators it can be a free convenient option. Example.

Here we will do a BIOS example as it is simpler on x86. But note that it is not the most robust method.

main.S

.code16
    mov $msg, %si
    mov $0x0e, %ah
loop:
    lodsb
    or %al, %al
    jz halt
    int $0x10
    jmp loop
halt:
    hlt
msg:
    .asciz "hello world"

GitHub upstream.

link.ld

SECTIONS
{
    /* The BIOS loads the code from the disk to this location.
     * We must tell that to the linker so that it can properly
     * calculate the addresses of symbols we might jump to.
     */
    . = 0x7c00;
    .text :
    {
        __start = .;
        *(.text)
        /* Place the magic boot bytes at the end of the first 512 sector. */
        . = 0x1FE;
        SHORT(0xAA55)
    }
}

Assemble and link with:

as -g -o main.o main.S
ld --oformat binary -o main.img -T link.ld main.o
qemu-system-x86_64 -hda main.img

Outcome:

And on the T430:

Tested on: Lenovo Thinkpad T430, UEFI BIOS 1.16. Disk generated on an Ubuntu 18.04 host.

Besides the standard userland assembly instructions, we have:

• .code16: tells GAS to output 16-bit code

• cli: disable software interrupts. Those could make the processor start running again after the hlt

• int $0x10: does a BIOS call. This is what prints the characters one by one.

The important link flags are:

• --oformat binary: output raw binary assembly code, don't wrap it inside an ELF file as is the case for regular userland executables.

To better understand the linker script part, familiarize yourself with the relocation step of linking: What do linkers do?

Cooler x86 bare metal programs

Here are a few more complex bare metal setups that I've achieved:

• multicore: What does multicore assembly language look like?
• paging: How does x86 paging work?

Use C instead of assembly

Summary: use GRUB multiboot, which will solve a lot of annoying problems you never thought about. See the section below.

The main difficulty on x86 is that the BIOS only loads 512 bytes from the disk to memory, and you are likely to blow up those 512 bytes when using C!

To solve that, we can use a two-stage bootloader. This makes further BIOS calls, which load more bytes from the disk into memory. Here is a minimal stage 2 assembly example from scratch using the int 0x13 BIOS calls:

Alternatively:

• if you only need it to work in QEMU but not real hardware, use the -kernel option, which loads an entire ELF file into memory. Here is an ARM example I've created with that method.
• for the Raspberry Pi, the default firmware takes care of the image loading for us from an ELF file named kernel7.img, much like QEMU -kernel does.

For educational purposes only, here is a one stage minimal C example:

main.c

void main(void) {
    int i;
    char s[] = {'h', 'e', 'l', 'l', 'o', ' ', 'w', 'o', 'r', 'l', 'd'};
    for (i = 0; i < sizeof(s); ++i) {
        __asm__ (
            "int $0x10" : : "a" ((0x0e << 8) | s[i])
        );
    }
    while (1) {
        __asm__ ("hlt");
    };
}

entry.S

.code16
.text
.global mystart
mystart:
    ljmp $0, $.setcs
.setcs:
    xor %ax, %ax
    mov %ax, %ds
    mov %ax, %es
    mov %ax, %ss
    mov $__stack_top, %esp
    cld
    call main

linker.ld

ENTRY(mystart)
SECTIONS
{
  . = 0x7c00;
  .text : {
    entry.o(.text)
    *(.text)
    *(.data)
    *(.rodata)
    __bss_start = .;
    /* COMMON vs BSS: https://stackoverflow.com/questions/16835716/bss-vs-common-what-goes-where */
    *(.bss)
    *(COMMON)
    __bss_end = .;
  }
  /* https://stackoverflow.com/questions/53584666/why-does-gnu-ld-include-a-section-that-does-not-appear-in-the-linker-script */
  .sig : AT(ADDR(.text) + 512 - 2)
  {
      SHORT(0xaa55);
  }
  /DISCARD/ : {
    *(.eh_frame)
  }
  __stack_bottom = .;
  . = . + 0x1000;
  __stack_top = .;
}

run

set -eux
as -ggdb3 --32 -o entry.o entry.S
gcc -c -ggdb3 -m16 -ffreestanding -fno-PIE -nostartfiles -nostdlib -o main.o -std=c99 main.c
ld -m elf_i386 -o main.elf -T linker.ld entry.o main.o
objcopy -O binary main.elf main.img
qemu-system-x86_64 -drive file=main.img,format=raw

C standard library

Things get more fun if you also want to use the C standard library however, since we don't have the Linux kernel, which implements much of the C standard library functionality through POSIX.

A few possibilities, without going to a full-blown OS like Linux, include:

• Write your own. It's just a bunch of headers and C files in the end, right? Right??

• Newlib

  Detailed example at: https://electronics.stackexchange.com/questions/223929/c-standard-libraries-on-bare-metal/223931

  Newlib implements all the boring non-OS specific things for you, e.g. memcmp, memcpy, etc.

  Then, it provides some stubs for you to implement the syscalls that you need yourself.

  For example, we can implement exit() on ARM through semihosting with:

  void _exit(int status) {
      __asm__ __volatile__ ("mov r0, #0x18; ldr r1, =#0x20026; svc 0x00123456");
  }
  

  as shown at in this example.

  For example, you could redirect printf to the UART or ARM systems, or implement exit() with semihosting.

• embedded operating systems like FreeRTOS and Zephyr.

  Such operating systems typically allow you to turn off pre-emptive scheduling, therefore giving you full control over the runtime of the program.

  They can be seen as a sort of pre-implemented Newlib.

GNU GRUB Multiboot

Boot sectors are simple, but they are not very convenient:

• you can only have one OS per disk
• the load code has to be really small and fit into 512 bytes
• you have to do a lot of startup yourself, like moving into protected mode

It is for those reasons that GNU GRUB created a more convenient file format called multiboot.

Minimal working example: https://github.com/cirosantilli/x86-bare-metal-examples/tree/d217b180be4220a0b4a453f31275d38e697a99e0/multiboot/hello-world

I also use it on my GitHub examples repo to be able to easily run all examples on real hardware without burning the USB a million times.

QEMU outcome:

T430:

If you prepare your OS as a multiboot file, GRUB is then able to find it inside a regular filesystem.

This is what most distros do, putting OS images under /boot.

Multiboot files are basically an ELF file with a special header. They are specified by GRUB at: https://www.gnu.org/software/grub/manual/multiboot/multiboot.html

You can turn a multiboot file into a bootable disk with grub-mkrescue.

Firmware

In truth, your boot sector is not the first software that runs on the system's CPU.

What actually runs first is the so-called firmware, which is a software:

• made by the hardware manufacturers
• typically closed source but likely C-based
• stored in read-only memory, and therefore harder / impossible to modify without the vendor's consent.

Well known firmwares include:

• BIOS: old all-present x86 firmware. SeaBIOS is the default open source implementation used by QEMU.
• UEFI: BIOS successor, better standardized, but more capable, and incredibly bloated.
• Coreboot: the noble cross arch open source attempt

The firmware does things like:

• loop over each hard disk, USB, network, etc. until you find something bootable.

  When we run QEMU, -hda says that main.img is a hard disk connected to the hardware, and hda is the first one to be tried, and it is used.

• load the first 512 bytes to RAM memory address 0x7c00, put the CPU's RIP there, and let it run

• show things like the boot menu or BIOS print calls on the display

Firmware offers OS-like functionality on which most OS-es depend. E.g. a Python subset has been ported to run on BIOS / UEFI: https://www.youtube.com/watch?v=bYQ_lq5dcvM

It can be argued that firmwares are indistinguishable from OSes, and that firmware is the only "true" bare metal programming one can do.

As this CoreOS dev puts it:

The hard part

When you power up a PC, the chips that make up the chipset (northbridge, southbridge and SuperIO) are not yet initialized properly. Even though the BIOS ROM is as far removed from the CPU as it could be, this is accessible by the CPU, because it has to be, otherwise the CPU would have no instructions to execute. This does not mean that BIOS ROM is completely mapped, usually not. But just enough is mapped to get the boot process going. Any other devices, just forget it.

When you run Coreboot under QEMU, you can experiment with the higher layers of Coreboot and with payloads, but QEMU offers little opportunity to experiment with the low level startup code. For one thing, RAM just works right from the start.

Post BIOS initial state

Like many things in hardware, standardization is weak, and one of the things you should not rely on is the initial state of registers when your code starts running after BIOS.

So do yourself a favor and use some initialization code like the following: https://stackoverflow.com/a/32509555/895245

Registers like %ds and %es have important side effects, so you should zero them out even if you are not using them explicitly.

Note that some emulators are nicer than real hardware and give you a nice initial state. Then when you go run on real hardware, everything breaks.

El Torito

Format that can be burnt to CDs: https://en.wikipedia.org/wiki/El_Torito_%28CD-ROM_standard%29

It is also possible to produce a hybrid image that works on either ISO or USB. This is can be done with grub-mkrescue (example), and is also done by the Linux kernel on make isoimage using isohybrid.

ARM

In ARM, the general ideas are the same.

There is no widely available semi-standardized pre-installed firmware like BIOS for us to use for the IO, so the two simplest types of IO that we can do are:

• serial, which is widely available on devboards
• blink the LED

I have uploaded:

• a few simple QEMU C + Newlib and raw assembly examples here on GitHub.

  The prompt.c example for example takes input from your host terminal and gives back output all through the simulated UART:

  enter a character
  got: a
  new alloc of 1 bytes at address 0x0x4000a1c0
  enter a character
  got: b
  new alloc of 2 bytes at address 0x0x4000a1c0
  enter a character
  

  See also: How to make bare metal ARM programs and run them on QEMU?

• a fully automated Raspberry Pi blinker setup at: https://github.com/cirosantilli/raspberry-pi-bare-metal-blinker

  

  See also: How to run a C program with no OS on the Raspberry Pi?

  To "see" the LEDs on QEMU you have to compile QEMU from source with a debug flag: https://raspberrypi.stackexchange.com/questions/56373/is-it-possible-to-get-the-state-of-the-leds-and-gpios-in-a-qemu-emulation-like-t

  Next, you should try a UART hello world. You can start from the blinker example, and replace the kernel with this one: https://github.com/dwelch67/raspberrypi/tree/bce377230c2cdd8ff1e40919fdedbc2533ef5a00/uart01

  First get the UART working with Raspbian as I've explained at: https://raspberrypi.stackexchange.com/questions/38/prepare-for-ssh-without-a-screen/54394#54394 It will look something like this:

  

  Make sure to use the right pins, or else you can burn your UART to USB converter, I've done it twice already by short circuiting ground and 5V...

  Finally connect to the serial from the host with:

  screen /dev/ttyUSB0 115200
  

  For the Raspberry Pi, we use a Micro SD card instead of an USB stick to contain our executable, for which you normally need an adapter to connect to your computer:

  

  Don't forget to unlock the SD adapter as shown at: https://askubuntu.com/questions/213889/microsd-card-is-set-to-read-only-state-how-can-i-write-data-on-it/814585#814585

  https://github.com/dwelch67/raspberrypi looks like the most popular bare metal Raspberry Pi tutorial available today.

Some differences from x86 include:

• IO is done by writing to magic addresses directly, there is no in and out instructions.

  This is called memory mapped IO.

• for some real hardware, like the Raspberry Pi, you can add the firmware (BIOS) yourself to the disk image.

  That is a good thing, as it makes updating that firmware more transparent.

Resources

• http://wiki.osdev.org is a great source for those matters.
• https://github.com/scanlime/metalkit is a more automated / general bare metal compilation system, that provides a tiny custom API

You can use pathlib. Unfortunately this is only available in the stdlib for Python 3.4. If you have an older version you'll have to install a copy from PyPI here. This should be easy to do using pip.

from pathlib import Path

p = Path(__file__).parents[1]

print(p)
# /absolute/path/to/two/levels/up

This uses the parents sequence which provides access to the parent directories and chooses the 2nd one up.

Note that p in this case will be some form of Path object, with their own methods. If you need the paths as string then you can call str on them.

I have researched on this for a couple of days and got the solution. Now in Android O you can set the background limitation as below

The service which is calling a service class

Intent serviceIntent = new Intent(SettingActivity.this,DetectedService.class);
if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.O) {
    SettingActivity.this.startForegroundService(serviceIntent);
} else {
    startService(serviceIntent);
}

and the service class should be like

public class DetectedService extends Service { 
    @Override
    public IBinder onBind(Intent intent) {
        return null;
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        return START_STICKY;
    }

    @Override
    public void onCreate() {
        super.onCreate();
        int NOTIFICATION_ID = (int) (System.currentTimeMillis()%10000);
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            startForeground(NOTIFICATION_ID, new Notification.Builder(this).build());
        }


        // Do whatever you want to do here
    }
}

System environment variables are globally accessed by all users.
User environment variables are specific only to the currently logged-in user.

Based on the answer of @AlokThakur (thanks!):

def run_system_command(command):
    return_value = os.system(command)
    # Calculate the return value code
    return_value = int(bin(return_value).replace("0b", "").rjust(16, '0')[:8], 2)
    if return_value != 0:
        raise RuntimeError(f'The system command\n{command}\nexited with return code {return_value}')

If you created the DLL using .net 4.5 , then copy and paste this command on command prompt.

 %SystemRoot%\Microsoft.NET\Framework\v4.0.30319\regasm.exe MyAssembly.dll

# echo ::memstat | mdb -k
Page Summary                Pages                MB  %Tot
------------     ----------------  ----------------  ----
Kernel                       7308                57   23%
Anon                         9055                70   29%
Exec and libs                1968                15    6%
Page cache                   2224                17    7%
Free (cachelist)             6470                50   20%
Free (freelist)              4641                36   15%

Total                       31666               247
Physical                    31256               244

POSIX defines a function: wait(NULL);. It's the shorthand for waitpid(-1, NULL, 0);, which will suspends the execution of the calling process until any one child process exits. Here, 1st argument of waitpid indicates wait for any child process to end.

In your case, have the parent call it from within your else branch.

You can look for this information in $_SERVER['HTTP_USER_AGENT'], but its format is free-form, not guaranteed to be sent, and could easily be altered by the user, whether for privacy or other reasons.

If you've not set the browsecap directive, this will return a warning. To make sure it's set, you can retrieve the value using ini_get and see if it's set.

if(ini_get("browscap")) {
    $browser = get_browser(null, true);
    $browser = get_browser($_SERVER['HTTP_USER_AGENT']);  
} 

As kba explained in his answer, your browser sends a lot of information to the server while loading a webpage. Most websites use these User-agent information to determine the visitor's operating system, browser and various information.

int a = fork(); 

Creates a duplicate process "clone?", which shares the execution stack. The difference between the parent and the child is the return value of the function.

The child getting 0 returned, and the parent getting the new pid.

Each time the addresses and the values of the stack variables are copied. The execution continues at the point it already got to in the code.

At each fork, only one value is modified - the return value from fork.

File descriptors

• To Kernel all open files are referred to by file descriptors.
• A file descriptor is a non - negative integer.
• When we open an existing or create a new file, the kernel returns a file descriptor to a process.
• When we want to read or write on a file, we identify the file with file descriptor that was retuned by open or create, as an argument to either read or write.
• Each UNIX process has 20 file descriptors and it disposal, numbered 0 through 19 but it was extended to 63 by many systems.
• The first three are already opened when the process begins 0: The standard input 1: The standard output 2: The standard error output
• When the parent process forks a process, the child process inherits the file descriptors of the parent

Here's a paper called "Writing a Simple Operating System From Scratch". It covers writing a bootloader, entering x86-32 protected mode, and writing a basic kernel in C. It seems to do a good job at explaining everything in detail.

Softwares run on the OS on a very simple premise - they require memory. The device OS provides it in the form of RAM. The amount of memory required may vary - some softwares need huge memory, some require paltry memory. Most (if not all) users run multiple applications on the OS simultaneously, and given that memory is expensive (and device size is finite), the amount of memory available is always limited. So given that all softwares require a certain amount of RAM, and all of them can be made to run at the same time, OS has to take care of two things:

1. That the software always runs until user aborts it, i.e. it should not auto-abort because OS has run out of memory.
2. The above activity, while maintaining a respectable performance for the softwares running.

Now the main question boils down to how the memory is being managed. What exactly governs where in the memory will the data belonging to a given software reside?

Possible solution 1: Let individual softwares specify explicitly the memory address they will use in the device. Suppose Photoshop declares that it will always use memory addresses ranging from 0 to 1023 (imagine the memory as a linear array of bytes, so first byte is at location 0, 1024th byte is at location 1023) - i.e. occupying 1 GB memory. Similarly, VLC declares that it will occupy memory range 1244 to 1876, etc.

Advantages:

1. Every application is pre-assigned a memory slot, so when it is installed and executed, it just stores its data in that memory area, and everything works fine.

Disadvantages:

1. This does not scale. Theoretically, an app may require a huge amount of memory when it is doing something really heavy-duty. So to ensure that it never runs out of memory, the memory area allocated to it must always be more than or equal to that amount of memory. What if a software, whose maximal theoretical memory usage is 2 GB (hence requiring 2 GB memory allocation from RAM), is installed in a machine with only 1 GB memory? Should the software just abort on startup, saying that the available RAM is less than 2 GB? Or should it continue, and the moment the memory required exceeds 2 GB, just abort and bail out with the message that not enough memory is available?

2. It is not possible to prevent memory mangling. There are millions of softwares out there, even if each of them was allotted just 1 kB memory, the total memory required would exceed 16 GB, which is more than most devices offer. How can, then, different softwares be allotted memory slots that do not encroach upon each other's areas? Firstly, there is no centralized software market which can regulate that when a new software is being released, it must assign itself this much memory from this yet unoccupied area, and secondly, even if there were, it is not possible to do it because the no. of softwares is practically infinite (thus requiring infinite memory to accommodate all of them), and the total RAM available on any device is not sufficient to accommodate even a fraction of what is required, thus making inevitable the encroaching of the memory bounds of one software upon that of another. So what happens when Photoshop is assigned memory locations 1 to 1023 and VLC is assigned 1000 to 1676? What if Photoshop stores some data at location 1008, then VLC overwrites that with its own data, and later Photoshop accesses it thinking that it is the same data is had stored there previously? As you can imagine, bad things will happen.

So clearly, as you can see, this idea is rather naive.

Possible solution 2: Let's try another scheme - where OS will do majority of the memory management. Softwares, whenever they require any memory, will just request the OS, and the OS will accommodate accordingly. Say OS ensures that whenever a new process is requesting for memory, it will allocate the memory from the lowest byte address possible (as said earlier, RAM can be imagined as a linear array of bytes, so for a 4 GB RAM, the addresses range for a byte from 0 to 2^32-1) if the process is starting, else if it is a running process requesting the memory, it will allocate from the last memory location where that process still resides. Since the softwares will be emitting addresses without considering what the actual memory address is going to be where that data is stored, OS will have to maintain a mapping, per software, of the address emitted by the software to the actual physical address (Note: that is one of the two reasons we call this concept Virtual Memory. Softwares are not caring about the real memory address where their data are getting stored, they just spit out addresses on the fly, and the OS finds the right place to fit it and find it later if required).

Say the device has just been turned on, OS has just launched, right now there is no other process running (ignoring the OS, which is also a process!), and you decide to launch VLC. So VLC is allocated a part of the RAM from the lowest byte addresses. Good. Now while the video is running, you need to start your browser to view some webpage. Then you need to launch Notepad to scribble some text. And then Eclipse to do some coding.. Pretty soon your memory of 4 GB is all used up, and the RAM looks like this:

Problem 1: Now you cannot start any other process, for all RAM is used up. Thus programs have to be written keeping the maximum memory available in mind (practically even less will be available, as other softwares will be running parallelly as well!). In other words, you cannot run a high-memory consuming app in your ramshackle 1 GB PC.

Okay, so now you decide that you no longer need to keep Eclipse and Chrome open, you close them to free up some memory. The space occupied in RAM by those processes is reclaimed by OS, and it looks like this now:

Suppose that closing these two frees up 700 MB space - (400 + 300) MB. Now you need to launch Opera, which will take up 450 MB space. Well, you do have more than 450 MB space available in total, but...it is not contiguous, it is divided into individual chunks, none of which is big enough to fit 450 MB. So you hit upon a brilliant idea, let's move all the processes below to as much above as possible, which will leave the 700 MB empty space in one chunk at the bottom. This is called compaction. Great, except that...all the processes which are there are running. Moving them will mean moving the address of all their contents (remember, OS maintains a mapping of the memory spat out by the software to the actual memory address. Imagine software had spat out an address of 45 with data 123, and OS had stored it in location 2012 and created an entry in the map, mapping 45 to 2012. If the software is now moved in memory, what used to be at location 2012 will no longer be at 2012, but in a new location, and OS has to update the map accordingly to map 45 to the new address, so that the software can get the expected data (123) when it queries for memory location 45. As far as the software is concerned, all it knows is that address 45 contains the data 123!)! Imagine a process that is referencing a local variable i. By the time it is accessed again, its address has changed, and it won't be able to find it any more. The same will hold for all functions, objects, variables, basically everything has an address, and moving a process will mean changing the address of all of them. Which leads us to:

Problem 2: You cannot move a process. The values of all variables, functions and objects within that process have hardcoded values as spat out by the compiler during compilation, the process depends on them being at the same location during its lifetime, and changing them is expensive. As a result, processes leave behind big "holes" when they exit. This is called External Fragmentation.

Fine. Suppose somehow, by some miraculous manner, you do manage to move the processes up. Now there is 700 MB of free space at the bottom:

Opera smoothly fits in at the bottom. Now your RAM looks like this:

Good. Everything is looking fine. However, there is not much space left, and now you need to launch Chrome again, a known memory-hog! It needs lots of memory to start, and you have hardly any left...Except.. you now notice that some of the processes, which were initially occupying large space, now is not needing much space. May be you have stopped your video in VLC, hence it is still occupying some space, but not as much as it required while running a high resolution video. Similarly for Notepad and Photos. Your RAM now looks like this:

Holes, once again! Back to square one! Except, previously, the holes occurred due to processes terminating, now it is due to processes requiring less space than before! And you again have the same problem, the holes combined yield more space than required, but they are scattered around, not much of use in isolation. So you have to move those processes again, an expensive operation, and a very frequent one at that, since processes will frequently reduce in size over their lifetime.

Problem 3: Processes, over their lifetime, may reduce in size, leaving behind unused space, which if needed to be used, will require the expensive operation of moving many processes. This is called Internal Fragmentation.

Fine, so now, your OS does the required thing, moves processes around and start Chrome and after some time, your RAM looks like this:

Cool. Now suppose you again resume watching Avatar in VLC. Its memory requirement will shoot up! But...there is no space left for it to grow, as Notepad is snuggled at its bottom. So, again, all processes has to move below until VLC has found sufficient space!

Problem 4: If processes needs to grow, it will be a very expensive operation

Fine. Now suppose, Photos is being used to load some photos from an external hard disk. Accessing hard-disk takes you from the realm of caches and RAM to that of disk, which is slower by orders of magnitudes. Painfully, irrevocably, transcendentally slower. It is an I/O operation, which means it is not CPU bound (it is rather the exact opposite), which means it does not need to occupy RAM right now. However, it still occupies RAM stubbornly. If you want to launch Firefox in the meantime, you can't, because there is not much memory available, whereas if Photos was taken out of memory for the duration of its I/O bound activity, it would have freed lot of memory, followed by (expensive) compaction, followed by Firefox fitting in.

Problem 5: I/O bound jobs keep on occupying RAM, leading to under-utilization of RAM, which could have been used by CPU bound jobs in the meantime.

So, as we can see, we have so many problems even with the approach of virtual memory.

There are two approaches to tackle these problems - paging and segmentation. Let us discuss paging. In this approach, the virtual address space of a process is mapped to the physical memory in chunks - called pages. A typical page size is 4 kB. The mapping is maintained by something called a page table, given a virtual address, all now we have to do is find out which page the address belong to, then from the page table, find the corresponding location for that page in actual physical memory (known as frame), and given that the offset of the virtual address within the page is same for the page as well as the frame, find out the actual address by adding that offset to the address returned by the page table. For example:

On the left is the virtual address space of a process. Say the virtual address space requires 40 units of memory. If the physical address space (on the right) had 40 units of memory as well, it would have been possible to map all location from the left to a location on the right, and we would have been so happy. But as ill luck would have it, not only does the physical memory have less (24 here) memory units available, it has to be shared between multiple processes as well! Fine, let's see how we make do with it.

When the process starts, say a memory access request for location 35 is made. Here the page size is 8 (each page contains 8 locations, the entire virtual address space of 40 locations thus contains 5 pages). So this location belongs to page no. 4 (35/8). Within this page, this location has an offset of 3 (35%8). So this location can be specified by the tuple (pageIndex, offset) = (4,3). This is just the starting, so no part of the process is stored in the actual physical memory yet. So the page table, which maintains a mapping of the pages on the left to the actual pages on the right (where they are called frames) is currently empty. So OS relinquishes the CPU, lets a device driver access the disk and fetch the page no. 4 for this process (basically a memory chunk from the program on the disk whose addresses range from 32 to 39). When it arrives, OS allocates the page somewhere in the RAM, say first frame itself, and the page table for this process takes note that page 4 maps to frame 0 in the RAM. Now the data is finally there in the physical memory. OS again queries the page table for the tuple (4,3), and this time, page table says that page 4 is already mapped to frame 0 in the RAM. So OS simply goes to the 0th frame in RAM, accesses the data at offset 3 in that frame (Take a moment to understand this. The entire page, which was fetched from disk, is moved to frame. So whatever the offset of an individual memory location in a page was, it will be the same in the frame as well, since within the page/frame, the memory unit still resides at the same place relatively!), and returns the data! Because the data was not found in memory at first query itself, but rather had to be fetched from disk to be loaded into memory, it constitutes a miss.

Fine. Now suppose, a memory access for location 28 is made. It boils down to (3,4). Page table right now has only one entry, mapping page 4 to frame 0. So this is again a miss, the process relinquishes the CPU, device driver fetches the page from disk, process regains control of CPU again, and its page table is updated. Say now the page 3 is mapped to frame 1 in the RAM. So (3,4) becomes (1,4), and the data at that location in RAM is returned. Good. In this way, suppose the next memory access is for location 8, which translates to (1,0). Page 1 is not in memory yet, the same procedure is repeated, and the page is allocated at frame 2 in RAM. Now the RAM-process mapping looks like the picture above. At this point in time, the RAM, which had only 24 units of memory available, is filled up. Suppose the next memory access request for this process is from address 30. It maps to (3,6), and page table says that page 3 is in RAM, and it maps to frame 1. Yay! So the data is fetched from RAM location (1,6), and returned. This constitutes a hit, as data required can be obtained directly from RAM, thus being very fast. Similarly, the next few access requests, say for locations 11, 32, 26, 27 all are hits, i.e. data requested by the process is found directly in the RAM without needing to look elsewhere.

Now suppose a memory access request for location 3 comes. It translates to (0,3), and page table for this process, which currently has 3 entries, for pages 1, 3 and 4 says that this page is not in memory. Like previous cases, it is fetched from disk, however, unlike previous cases, RAM is filled up! So what to do now? Here lies the beauty of virtual memory, a frame from the RAM is evicted! (Various factors govern which frame is to be evicted. It may be LRU based, where the frame which was least recently accessed for a process is to be evicted. It may be first-come-first-evicted basis, where the frame which allocated longest time ago, is evicted, etc.) So some frame is evicted. Say frame 1 (just randomly choosing it). However, that frame is mapped to some page! (Currently, it is mapped by the page table to page 3 of our one and only one process). So that process has to be told this tragic news, that one frame, which unfortunate belongs to you, is to be evicted from RAM to make room for another pages. The process has to ensure that it updates its page table with this information, that is, removing the entry for that page-frame duo, so that the next time a request is made for that page, it right tells the process that this page is no longer in memory, and has to be fetched from disk. Good. So frame 1 is evicted, page 0 is brought in and placed there in the RAM, and the entry for page 3 is removed, and replaced by page 0 mapping to the same frame 1. So now our mapping looks like this (note the colour change in the second frame on the right side):

Saw what just happened? The process had to grow, it needed more space than the available RAM, but unlike our earlier scenario where every process in the RAM had to move to accommodate a growing process, here it happened by just one page replacement! This was made possible by the fact that the memory for a process no longer needs to be contiguous, it can reside at different places in chunks, OS maintains the information as to where they are, and when required, they are appropriately queried. Note: you might be thinking, huh, what if most of the times it is a miss, and the data has to be constantly loaded from disk into memory? Yes, theoretically, it is possible, but most compilers are designed in such a manner that follows locality of reference, i.e. if data from some memory location is used, the next data needed will be located somewhere very close, perhaps from the same page, the page which was just loaded into memory. As a result, the next miss will happen after quite some time, most of the upcoming memory requirements will be met by the page just brought in, or the pages already in memory which were recently used. The exact same principle allows us to evict the least recently used page as well, with the logic that what has not been used in a while, is not likely to be used in a while as well. However, it is not always so, and in exceptional cases, yes, performance may suffer. More about it later.

Solution to Problem 4: Processes can now grow easily, if space problem is faced, all it requires is to do a simple page replacement, without moving any other process.

Solution to Problem 1: A process can access unlimited memory. When more memory than available is needed, the disk is used as backup, the new data required is loaded into memory from the disk, and the least recently used data frame (or page) is moved to disk. This can go on infinitely, and since disk space is cheap and virtually unlimited, it gives an illusion of unlimited memory. Another reason for the name Virtual Memory, it gives you illusion of memory which is not really available!

Cool. Earlier we were facing a problem where even though a process reduces in size, the empty space is difficult to be reclaimed by other processes (because it would require costly compaction). Now it is easy, when a process becomes smaller in size, many of its pages are no longer used, so when other processes need more memory, a simple LRU based eviction automatically evicts those less-used pages from RAM, and replaces them with the new pages from the other processes (and of course updating the page tables of all those processes as well as the original process which now requires less space), all these without any costly compaction operation!

Solution to Problem 3: Whenever processes reduce in size, its frames in RAM will be less used, so a simple LRU based eviction can evict those pages out and replace them with pages required by new processes, thus avoiding Internal Fragmentation without need for compaction.

As for problem 2, take a moment to understand this, the scenario itself is completely removed! There is no need to move a process to accommodate a new process, because now the entire process never needs to fit at once, only certain pages of it need to fit ad hoc, that happens by evicting frames from RAM. Everything happens in units of pages, thus there is no concept of hole now, and hence no question of anything moving! May be 10 pages had to be moved because of this new requirement, there are thousands of pages which are left untouched. Whereas, earlier, all processes (every bit of them) had to be moved!

Solution to Problem 2: To accommodate a new process, data from only less recently used parts of other processes have to be evicted as required, and this happens in fixed size units called pages. Thus there is no possibility of hole or External Fragmentation with this system.

Now when the process needs to do some I/O operation, it can relinquish CPU easily! OS simply evicts all its pages from the RAM (perhaps store it in some cache) while new processes occupy the RAM in the meantime. When the I/O operation is done, OS simply restores those pages to the RAM (of course by replacing the pages from some other processes, may be from the ones which replaced the original process, or may be from some which themselves need to do I/O now, and hence can relinquish the memory!)

Solution to Problem 5: When a process is doing I/O operations, it can easily give up RAM usage, which can be utilized by other processes. This leads to proper utilization of RAM.

And of course, now no process is accessing the RAM directly. Each process is accessing a virtual memory location, which is mapped to a physical RAM address and maintained by the page-table of that process. The mapping is OS-backed, OS lets the process know which frame is empty so that a new page for a process can be fitted there. Since this memory allocation is overseen by the OS itself, it can easily ensure that no process encroaches upon the contents of another process by allocating only empty frames from RAM, or upon encroaching upon the contents of another process in the RAM, communicate to the process to update it page-table.

Solution to Original Problem: There is no possibility of a process accessing the contents of another process, since the entire allocation is managed by the OS itself, and every process runs in its own sandboxed virtual address space.

So paging (among other techniques), in conjunction with virtual memory, is what powers today's softwares running on OS-es! This frees the software developer from worrying about how much memory is available on the user's device, where to store the data, how to prevent other processes from corrupting their software's data, etc. However, it is of course, not full-proof. There are flaws:

1. Paging is, ultimately, giving user the illusion of infinite memory by using disk as secondary backup. Retrieving data from secondary storage to fit into memory (called page swap, and the event of not finding the desired page in RAM is called page fault) is expensive as it is an IO operation. This slows down the process. Several such page swaps happen in succession, and the process becomes painfully slow. Ever seen your software running fine and dandy, and suddenly it becomes so slow that it nearly hangs, or leaves you with no option that to restart it? Possibly too many page swaps were happening, making it slow (called thrashing).

So coming back to OP,

Why do we need the virtual memory for executing a process? - As the answer explains at length, to give softwares the illusion of the device/OS having infinite memory, so that any software, big or small, can be run, without worrying about memory allocation, or other processes corrupting its data, even when running in parallel. It is a concept, implemented in practice through various techniques, one of which, as described here, is Paging. It may also be Segmentation.

Where does this virtual memory stand when the process (program) from the external hard drive is brought to the main memory (physical memory) for the execution? - Virtual memory doesn't stand anywhere per se, it is an abstraction, always present, when the software/process/program is booted, a new page table is created for it, and it contains the mapping from the addresses spat out by that process to the actual physical address in RAM. Since the addresses spat out by the process are not real addresses, in one sense, they are, actually, what you can say, the virtual memory.

Who takes care of the virtual memory and what is the size of the virtual memory? - It is taken care of by, in tandem, the OS and the software. Imagine a function in your code (which eventually compiled and made into the executable that spawned the process) which contains a local variable - an int i. When the code executes, i gets a memory address within the stack of the function. That function is itself stored as an object somewhere else. These addresses are compiler generated (the compiler which compiled your code into the executable) - virtual addresses. When executed, i has to reside somewhere in actual physical address for duration of that function at least (unless it is a static variable!), so OS maps the compiler generated virtual address of i into an actual physical address, so that whenever, within that function, some code requires the value of i, that process can query the OS for that virtual address, and OS in turn can query the physical a

A small example of what you're trying to achieve would probably be a class similar to what's underneath:

import java.util.Locale;

public class OperatingSystem
{
    private static String OS = System.getProperty("os.name", "unknown").toLowerCase(Locale.ROOT);

    public static boolean isWindows()
    {
        return OS.contains("win");
    }

    public static boolean isMac()
    {
        return OS.contains("mac");
    }

    public static boolean isUnix()
    {
        return OS.contains("nux");
    }
}

This particular implementation is quite reliable and should be universally applicable. Just copy and paste it into your class of choice.

You have here available an example of DNS Caching in Debian using dnsmasq.

Configuration summary:

/etc/default/dnsmasq

# Ensure you add this line
DNSMASQ_OPTS="-r /etc/resolv.dnsmasq"

/etc/resolv.dnsmasq

# Your preferred servers
nameserver 1.1.1.1
nameserver 8.8.8.8
nameserver 2001:4860:4860::8888

/etc/resolv.conf

nameserver 127.0.0.1

Then just restart dnsmasq.

Benchmark test using DNS 1.1.1.1:

for i in {1..100}; do time dig slashdot.org @1.1.1.1; done 2>&1 | grep ^real | sed -e s/.*m// | awk '{sum += $1} END {print sum / NR}'

Benchmark test using you local cached DNS:

for i in {1..100}; do time dig slashdot.org; done 2>&1 | grep ^real | sed -e s/.*m// | awk '{sum += $1} END {print sum / NR}'

I did not find Haiku definition here. To be complete, Haiku-os definition is simple __HAIKU__

From here

    OperatingSystemMXBean operatingSystemMXBean = (OperatingSystemMXBean) ManagementFactory.getOperatingSystemMXBean();
    RuntimeMXBean runtimeMXBean = ManagementFactory.getRuntimeMXBean();
    int availableProcessors = operatingSystemMXBean.getAvailableProcessors();
    long prevUpTime = runtimeMXBean.getUptime();
    long prevProcessCpuTime = operatingSystemMXBean.getProcessCpuTime();
    double cpuUsage;
    try
    {
        Thread.sleep(500);
    }
    catch (Exception ignored) { }

    operatingSystemMXBean = (OperatingSystemMXBean) ManagementFactory.getOperatingSystemMXBean();
    long upTime = runtimeMXBean.getUptime();
    long processCpuTime = operatingSystemMXBean.getProcessCpuTime();
    long elapsedCpu = processCpuTime - prevProcessCpuTime;
    long elapsedTime = upTime - prevUpTime;

    cpuUsage = Math.min(99F, elapsedCpu / (elapsedTime * 10000F * availableProcessors));
    System.out.println("Java CPU: " + cpuUsage);

You can use this helper class;

using System;
using System.Runtime.InteropServices;

/// <summary>
/// Provides detailed information about the host operating system.
/// </summary>
public static class OSInfo
{
    #region BITS
    /// <summary>
    /// Determines if the current application is 32 or 64-bit.
    /// </summary>
    public static int Bits
    {
        get
        {
            return IntPtr.Size * 8;
        }
    }
    #endregion BITS

    #region EDITION
    private static string s_Edition;
    /// <summary>
    /// Gets the edition of the operating system running on this computer.
    /// </summary>
    public static string Edition
    {
        get
        {
            if (s_Edition != null)
                return s_Edition;  //***** RETURN *****//

            string edition = String.Empty;

            OperatingSystem osVersion = Environment.OSVersion;
            OSVERSIONINFOEX osVersionInfo = new OSVERSIONINFOEX();
            osVersionInfo.dwOSVersionInfoSize = Marshal.SizeOf( typeof( OSVERSIONINFOEX ) );

            if (GetVersionEx( ref osVersionInfo ))
            {
                int majorVersion = osVersion.Version.Major;
                int minorVersion = osVersion.Version.Minor;
                byte productType = osVersionInfo.wProductType;
                short suiteMask = osVersionInfo.wSuiteMask;

                #region VERSION 4
                if (majorVersion == 4)
                {
                    if (productType == VER_NT_WORKSTATION)
                    {
                        // Windows NT 4.0 Workstation
                        edition = "Workstation";
                    }
                    else if (productType == VER_NT_SERVER)
                    {
                        if ((suiteMask & VER_SUITE_ENTERPRISE) != 0)
                        {
                            // Windows NT 4.0 Server Enterprise
                            edition = "Enterprise Server";
                        }
                        else
                        {
                            // Windows NT 4.0 Server
                            edition = "Standard Server";
                        }
                    }
                }
                #endregion VERSION 4

                #region VERSION 5
                else if (majorVersion == 5)
                {
                    if (productType == VER_NT_WORKSTATION)
                    {
                        if ((suiteMask & VER_SUITE_PERSONAL) != 0)
                        {
                            // Windows XP Home Edition
                            edition = "Home";
                        }
                        else
                        {
                            // Windows XP / Windows 2000 Professional
                            edition = "Professional";
                        }
                    }
                    else if (productType == VER_NT_SERVER)
                    {
                        if (minorVersion == 0)
                        {
                            if ((suiteMask & VER_SUITE_DATACENTER) != 0)
                            {
                                // Windows 2000 Datacenter Server
                                edition = "Datacenter Server";
                            }
                            else if ((suiteMask & VER_SUITE_ENTERPRISE) != 0)
                            {
                                // Windows 2000 Advanced Server
                                edition = "Advanced Server";
                            }
                            else
                            {
                                // Windows 2000 Server
                                edition = "Server";
                            }
                        }
                        else
                        {
                            if ((suiteMask & VER_SUITE_DATACENTER) != 0)
                            {
                                // Windows Server 2003 Datacenter Edition
                                edition = "Datacenter";
                            }
                            else if ((suiteMask & VER_SUITE_ENTERPRISE) != 0)
                            {
                                // Windows Server 2003 Enterprise Edition
                                edition = "Enterprise";
                            }
                            else if ((suiteMask & VER_SUITE_BLADE) != 0)
                            {
                                // Windows Server 2003 Web Edition
                                edition = "Web Edition";
                            }
                            else
                            {
                                // Windows Server 2003 Standard Edition
                                edition = "Standard";
                            }
                        }
                    }
                }
                #endregion VERSION 5

                #region VERSION 6
                else if (majorVersion == 6)
                {
                    int ed;
                    if (GetProductInfo( majorVersion, minorVersion,
                        osVersionInfo.wServicePackMajor, osVersionInfo.wServicePackMinor,
                        out ed ))
                    {
                        switch (ed)
                        {
                            case PRODUCT_BUSINESS:
                                edition = "Business";
                                break;
                            case PRODUCT_BUSINESS_N:
                                edition = "Business N";
                                break;
                            case PRODUCT_CLUSTER_SERVER:
                                edition = "HPC Edition";
                                break;
                            case PRODUCT_DATACENTER_SERVER:
                                edition = "Datacenter Server";
                                break;
                            case PRODUCT_DATACENTER_SERVER_CORE:
                                edition = "Datacenter Server (core installation)";
                                break;
                            case PRODUCT_ENTERPRISE:
                                edition = "Enterprise";
                                break;
                            case PRODUCT_ENTERPRISE_N:
                                edition = "Enterprise N";
                                break;
                            case PRODUCT_ENTERPRISE_SERVER:
                                edition = "Enterprise Server";
                                break;
                            case PRODUCT_ENTERPRISE_SERVER_CORE:
                                edition = "Enterprise Server (core installation)";
                                break;
                            case PRODUCT_ENTERPRISE_SERVER_CORE_V:
                                edition = "Enterprise Server without Hyper-V (core installation)";
                                break;
                            case PRODUCT_ENTERPRISE_SERVER_IA64:
                                edition = "Enterprise Server for Itanium-based Systems";
                                break;
                            case PRODUCT_ENTERPRISE_SERVER_V:
                                edition = "Enterprise Server without Hyper-V";
                                break;
                            case PRODUCT_HOME_BASIC:
                                edition = "Home Basic";
                                break;
                            case PRODUCT_HOME_BASIC_N:
                                edition = "Home Basic N";
                                break;
                            case PRODUCT_HOME_PREMIUM:
                                edition = "Home Premium";
                                break;
                            case PRODUCT_HOME_PREMIUM_N:
                                edition = "Home Premium N";
                                break;
                            case PRODUCT_HYPERV:
                                edition = "Microsoft Hyper-V Server";
                                break;
                            case PRODUCT_MEDIUMBUSINESS_SERVER_MANAGEMENT:
                                edition = "Windows Essential Business Management Server";
                                break;
                            case PRODUCT_MEDIUMBUSINESS_SERVER_MESSAGING:
                                edition = "Windows Essential Business Messaging Server";
                                break;
                            case PRODUCT_MEDIUMBUSINESS_SERVER_SECURITY:
                                edition = "Windows Essential Business Security Server";
                                break;
                            case PRODUCT_SERVER_FOR_SMALLBUSINESS:
                                edition = "Windows Essential Server Solutions";
                                break;
                            case PRODUCT_SERVER_FOR_SMALLBUSINESS_V:
                                edition = "Windows Essential Server Solutions without Hyper-V";
                                break;
                            case PRODUCT_SMALLBUSINESS_SERVER:
                                edition = "Windows Small Business Server";
                                break;
                            case PRODUCT_STANDARD_SERVER:
                                edition = "Standard Server";
                                break;
                            case PRODUCT_STANDARD_SERVER_CORE:
                                edition = "Standard Server (core installation)";
                                break;
                            case PRODUCT_STANDARD_SERVER_CORE_V:
                                edition = "Standard Server without Hyper-V (core installation)";
                                break;
                            case PRODUCT_STANDARD_SERVER_V:
                                edition = "Standard Server without Hyper-V";
                                break;
                            case PRODUCT_STARTER:
                                edition = "Starter";
                                break;
                            case PRODUCT_STORAGE_ENTERPRISE_SERVER:
                                edition = "Enterprise Storage Server";
                                break;
                            case PRODUCT_STORAGE_EXPRESS_SERVER:
                                edition = "Express Storage Server";
                                break;
                            case PRODUCT_STORAGE_STANDARD_SERVER:
                                edition = "Standard Storage Server";
                                break;
                            case PRODUCT_STORAGE_WORKGROUP_SERVER:
                                edition = "Workgroup Storage Server";
                                break;
                            case PRODUCT_UNDEFINED:
                                edition = "Unknown product";
                                break;
                            case PRODUCT_ULTIMATE:
                                edition = "Ultimate";
                                break;
                            case PRODUCT_ULTIMATE_N:
                                edition = "Ultimate N";
                                break;
                            case PRODUCT_WEB_SERVER:
                                edition = "Web Server";
                                break;
                            case PRODUCT_WEB_SERVER_CORE:
                                edition = "Web Server (core installation)";
                                break;
                        }
                    }
                }
                #endregion VERSION 6
            }

            s_Edition = edition;
            return edition;
        }
    }
    #endregion EDITION

    #region NAME
    private static string s_Name;
    /// <summary>
    /// Gets the name of the operating system running on this computer.
    /// </summary>
    public static string Name
    {
        get
        {
            if (s_Name != null)
                return s_Name;  //***** RETURN *****//

            string name = "unknown";

            OperatingSystem osVersion = Environment.OSVersion;
            OSVERSIONINFOEX osVersionInfo = new OSVERSIONINFOEX();
            osVersionInfo.dwOSVersionInfoSize = Marshal.SizeOf( typeof( OSVERSIONINFOEX ) );

            if (GetVersionEx( ref osVersionInfo ))
            {
                int majorVersion = osVersion.Version.Major;
                int minorVersion = osVersion.Version.Minor;

                switch (osVersion.Platform)
                {
                    case PlatformID.Win32Windows:
                        {
                            if (majorVersion == 4)
                            {
                                string csdVersion = osVersionInfo.szCSDVersion;
                                switch (minorVersion)
                                {
                                    case 0:
                                        if (csdVersion == "B" || csdVersion == "C")
                                            name = "Windows 95 OSR2";
                                        else
                                            name = "Windows 95";
                                        break;
                                    case 10:
                                        if (csdVersion == "A")
                                            name = "Windows 98 Second Edition";
                                        else
                                            name = "Windows 98";
                                        break;
                                    case 90:
                                        name = "Windows Me";
                                        break;
                                }
                            }
                            break;
                        }

                    case PlatformID.Win32NT:
                        {
                            byte productType = osVersionInfo.wProductType;

                            switch (majorVersion)
                            {
                                case 3:
                                    name = "Windows NT 3.51";
                                    break;
                                case 4:
                                    switch (productType)
                                    {
                                        case 1:
                                            name = "Windows NT 4.0";
                                            break;
                                        case 3:
                                            name = "Windows NT 4.0 Server";
                                            break;
                                    }
                                    break;
                                case 5:
                                    switch (minorVersion)
                                    {
                                        case 0:
                                            name = "Windows 2000";
                                            break;
                                        case 1:
                                            name = "Windows XP";
                                            break;
                                        case 2:
                                            name = "Windows Server 2003";
                                            break;
                                    }
                                    break;
                                case 6:
                                    switch (productType)
                                    {
                                        case 1:
                                            name = "Windows Vista";
                                            break;
                                        case 3:
                                            name = "Windows Server 2008";
                                            break;
                                    }
                                    break;
                            }
                            break;
                        }
                }
            }

            s_Name = name;
            return name;
        }
    }
    #endregion NAME

    #region PINVOKE
    #region GET
    #region PRODUCT INFO
    [DllImport( "Kernel32.dll" )]
    internal static extern bool GetProductInfo(
        int osMajorVersion,
        int osMinorVersion,
        int spMajorVersion,
        int spMinorVersion,
        out int edition );
    #endregion PRODUCT INFO

    #region VERSION
    [DllImport( "kernel32.dll" )]
    private static extern bool GetVersionEx( ref OSVERSIONINFOEX osVersionInfo );
    #endregion VERSION
    #endregion GET

    #region OSVERSIONINFOEX
    [StructLayout( LayoutKind.Sequential )]
    private struct OSVERSIONINFOEX
    {
        public int dwOSVersionInfoSize;
        public int dwMajorVersion;
        public int dwMinorVersion;
        public int dwBuildNumber;
        public int dwPlatformId;
        [MarshalAs( UnmanagedType.ByValTStr, SizeConst = 128 )]
        public string szCSDVersion;
        public short wServicePackMajor;
        public short wServicePackMinor;
        public short wSuiteMask;
        public byte wProductType;
        public byte wReserved;
    }
    #endregion OSVERSIONINFOEX

    #region PRODUCT
    private const int PRODUCT_UNDEFINED = 0x00000000;
    private const int PRODUCT_ULTIMATE = 0x00000001;
    private const int PRODUCT_HOME_BASIC = 0x00000002;
    private const int PRODUCT_HOME_PREMIUM = 0x00000003;
    private const int PRODUCT_ENTERPRISE = 0x00000004;
    private const int PRODUCT_HOME_BASIC_N = 0x00000005;
    private const int PRODUCT_BUSINESS = 0x00000006;
    private const int PRODUCT_STANDARD_SERVER = 0x00000007;
    private const int PRODUCT_DATACENTER_SERVER = 0x00000008;
    private const int PRODUCT_SMALLBUSINESS_SERVER = 0x00000009;
    private const int PRODUCT_ENTERPRISE_SERVER = 0x0000000A;
    private const int PRODUCT_STARTER = 0x0000000B;
    private const int PRODUCT_DATACENTER_SERVER_CORE = 0x0000000C;
    private const int PRODUCT_STANDARD_SERVER_CORE = 0x0000000D;
    private const int PRODUCT_ENTERPRISE_SERVER_CORE = 0x0000000E;
    private const int PRODUCT_ENTERPRISE_SERVER_IA64 = 0x0000000F;
    private const int PRODUCT_BUSINESS_N = 0x00000010;
    private const int PRODUCT_WEB_SERVER = 0x00000011;
    private const int PRODUCT_CLUSTER_SERVER = 0x00000012;
    private const int PRODUCT_HOME_SERVER = 0x00000013;
    private const int PRODUCT_STORAGE_EXPRESS_SERVER = 0x00000014;
    private const int PRODUCT_STORAGE_STANDARD_SERVER = 0x00000015;
    private const int PRODUCT_STORAGE_WORKGROUP_SERVER = 0x00000016;
    private const int PRODUCT_STORAGE_ENTERPRISE_SERVER = 0x00000017;
    private const int PRODUCT_SERVER_FOR_SMALLBUSINESS = 0x00000018;
    private const int PRODUCT_SMALLBUSINESS_SERVER_PREMIUM = 0x00000019;
    private const int PRODUCT_HOME_PREMIUM_N = 0x0000001A;
    private const int PRODUCT_ENTERPRISE_N = 0x0000001B;
    private const int PRODUCT_ULTIMATE_N = 0x0000001C;
    private const int PRODUCT_WEB_SERVER_CORE = 0x0000001D;
    private const int PRODUCT_MEDIUMBUSINESS_SERVER_MANAGEMENT = 0x0000001E;
    private const int PRODUCT_MEDIUMBUSINESS_SERVER_SECURITY = 0x0000001F;
    private const int PRODUCT_MEDIUMBUSINESS_SERVER_MESSAGING = 0x00000020;
    private const int PRODUCT_SERVER_FOR_SMALLBUSINESS_V = 0x00000023;
    private const int PRODUCT_STANDARD_SERVER_V = 0x00000024;
    private const int PRODUCT_ENTERPRISE_SERVER_V = 0x00000026;
    private const int PRODUCT_STANDARD_SERVER_CORE_V = 0x00000028;
    private const int PRODUCT_ENTERPRISE_SERVER_CORE_V = 0x00000029;
    private const int PRODUCT_HYPERV = 0x0000002A;
    #endregion PRODUCT

    #region VERSIONS
    private const int VER_NT_WORKSTATION = 1;
    private const int VER_NT_DOMAIN_CONTROLLER = 2;
    private const int VER_NT_SERVER = 3;
    private const int VER_SUITE_SMALLBUSINESS = 1;
    private const int VER_SUITE_ENTERPRISE = 2;
    private const int VER_SUITE_TERMINAL = 16;
    private const int VER_SUITE_DATACENTER = 128;
    private const int VER_SUITE_SINGLEUSERTS = 256;
    private const int VER_SUITE_PERSONAL = 512;
    private const int VER_SUITE_BLADE = 1024;
    #endregion VERSIONS
    #endregion PINVOKE

    #region SERVICE PACK
    /// <summary>
    /// Gets the service pack information of the operating system running on this computer.
    /// </summary>
    public static string ServicePack
    {
        get
        {
            string servicePack = String.Empty;
            OSVERSIONINFOEX osVersionInfo = new OSVERSIONINFOEX();

            osVersionInfo.dwOSVersionInfoSize = Marshal.SizeOf( typeof( OSVERSIONINFOEX ) );

            if (GetVersionEx( ref osVersionInfo ))
            {
                servicePack = osVersionInfo.szCSDVersion;
            }

            return servicePack;
        }
    }
    #endregion SERVICE PACK

    #region VERSION
    #region BUILD
    /// <summary>
    /// Gets the build version number of the operating system running on this computer.
    /// </summary>
    public static int BuildVersion
    {
        get
        {
            return Environment.OSVersion.Version.Build;
        }
    }
    #endregion BUILD

    #region FULL
    #region STRING
    /// <summary>
    /// Gets the full version string of the operating system running on this computer.
    /// </summary>
    public static string VersionString
    {
        get
        {
            return Environment.OSVersion.Version.ToString();
        }
    }
    #endregion STRING

    #region VERSION
    /// <summary>
    /// Gets the full version of the operating system running on this computer.
    /// </summary>
    public static Version Version
    {
        get
        {
            return Environment.OSVersion.Version;
        }
    }
    #endregion VERSION
    #endregion FULL

    #region MAJOR
    /// <summary>
    /// Gets the major version number of the operating system running on this computer.
    /// </summary>
    public static int MajorVersion
    {
        get
        {
            return Environment.OSVersion.Version.Major;
        }
    }
    #endregion MAJOR

    #region MINOR
    /// <summary>
    /// Gets the minor version number of the operating system running on this computer.
    /// </summary>
    public static int MinorVersion
    {
        get
        {
            return Environment.OSVersion.Version.Minor;
        }
    }
    #endregion MINOR

    #region REVISION
    /// <summary>
    /// Gets the revision version number of the operating system running on this computer.
    /// </summary>
    public static int RevisionVersion
    {
        get
        {
            return Environment.OSVersion.Version.Revision;
        }
    }
    #endregion REVISION
    #endregion VERSION
}

Sample code is here:

    Console.WriteLine( "Operation System Information" );
    Console.WriteLine( "----------------------------" );
    Console.WriteLine( "Name = {0}", OSInfo.Name );
    Console.WriteLine( "Edition = {0}", OSInfo.Edition );
    Console.WriteLine( "Service Pack = {0}", OSInfo.ServicePack );
    Console.WriteLine( "Version = {0}", OSInfo.VersionString );
    Console.WriteLine( "Bits = {0}", OSInfo.Bits );

I was found at this address : http://www.csharp411.com/wp-content/uploads/2009/01/OSInfo.cs

The short answer to this question is that none of these values are a reliable indicator of how much memory an executable is actually using, and none of them are really appropriate for debugging a memory leak.

Private Bytes refer to the amount of memory that the process executable has asked for - not necessarily the amount it is actually using. They are "private" because they (usually) exclude memory-mapped files (i.e. shared DLLs). But - here's the catch - they don't necessarily exclude memory allocated by those files. There is no way to tell whether a change in private bytes was due to the executable itself, or due to a linked library. Private bytes are also not exclusively physical memory; they can be paged to disk or in the standby page list (i.e. no longer in use, but not paged yet either).

Working Set refers to the total physical memory (RAM) used by the process. However, unlike private bytes, this also includes memory-mapped files and various other resources, so it's an even less accurate measurement than the private bytes. This is the same value that gets reported in Task Manager's "Mem Usage" and has been the source of endless amounts of confusion in recent years. Memory in the Working Set is "physical" in the sense that it can be addressed without a page fault; however, the standby page list is also still physically in memory but not reported in the Working Set, and this is why you might see the "Mem Usage" suddenly drop when you minimize an application.

Virtual Bytes are the total virtual address space occupied by the entire process. This is like the working set, in the sense that it includes memory-mapped files (shared DLLs), but it also includes data in the standby list and data that has already been paged out and is sitting in a pagefile on disk somewhere. The total virtual bytes used by every process on a system under heavy load will add up to significantly more memory than the machine actually has.

So the relationships are:

• Private Bytes are what your app has actually allocated, but include pagefile usage;
• Working Set is the non-paged Private Bytes plus memory-mapped files;
• Virtual Bytes are the Working Set plus paged Private Bytes and standby list.

There's another problem here; just as shared libraries can allocate memory inside your application module, leading to potential false positives reported in your app's Private Bytes, your application may also end up allocating memory inside the shared modules, leading to false negatives. That means it's actually possible for your application to have a memory leak that never manifests itself in the Private Bytes at all. Unlikely, but possible.

Private Bytes are a reasonable approximation of the amount of memory your executable is using and can be used to help narrow down a list of potential candidates for a memory leak; if you see the number growing and growing constantly and endlessly, you would want to check that process for a leak. This cannot, however, prove that there is or is not a leak.

One of the most effective tools for detecting/correcting memory leaks in Windows is actually Visual Studio (link goes to page on using VS for memory leaks, not the product page). Rational Purify is another possibility. Microsoft also has a more general best practices document on this subject. There are more tools listed in this previous question.

I hope this clears a few things up! Tracking down memory leaks is one of the most difficult things to do in debugging. Good luck.

would take time to route through TeamViewer's servers (TeamViewer bypasses corporate Symmetric NATs by simply proxying traffic through their servers)

You'll find that TeamViewer rarely needs to relay traffic through their own servers. TeamViewer penetrates NAT and networks complicated by NAT using NAT traversal (I think it is UDP hole-punching, like Google's libjingle).

They do use their own servers to middle-man in order to do the handshake and connection set-up, but most of the time the relationship between client and server will be P2P (best case, when the hand-shake is successful). If NAT traversal fails, then TeamViewer will indeed relay traffic through its own servers.

I've only ever seen it do this when a client has been behind double-NAT, though.

These are two different modes in which your computer can operate. Prior to this, when computers were like a big room, if something crashes – it halts the whole computer. So computer architects decide to change it. Modern microprocessors implement in hardware at least 2 different states.

User mode:

• mode where all user programs execute. It does not have access to RAM and hardware. The reason for this is because if all programs ran in kernel mode, they would be able to overwrite each other’s memory. If it needs to access any of these features – it makes a call to the underlying API. Each process started by windows except of system process runs in user mode.

Kernel mode:

• mode where all kernel programs execute (different drivers). It has access to every resource and underlying hardware. Any CPU instruction can be executed and every memory address can be accessed. This mode is reserved for drivers which operate on the lowest level

How the switch occurs.

The switch from user mode to kernel mode is not done automatically by CPU. CPU is interrupted by interrupts (timers, keyboard, I/O). When interrupt occurs, CPU stops executing the current running program, switch to kernel mode, executes interrupt handler. This handler saves the state of CPU, performs its operations, restore the state and returns to user mode.

http://en.wikibooks.org/wiki/Windows_Programming/User_Mode_vs_Kernel_Mode

http://tldp.org/HOWTO/KernelAnalysis-HOWTO-3.html

http://en.wikipedia.org/wiki/Direct_memory_access

http://en.wikipedia.org/wiki/Interrupt_request

I can't comment on @Ian Ippolito answer (because I would have if I had the rep) but according to the document his comment linked, I'm fairly certain you can find the Chrome version for IOS. https://developer.chrome.com/multidevice/user-agent?hl=ja lists the UA as: Mozilla/5.0 (iPhone; CPU iPhone OS 10_3 like Mac OS X) AppleWebKit/602.1.50 (KHTML, like Gecko) CriOS/56.0.2924.75 Mobile/14E5239e Safari/602.1

So this should work:

if ((verOffset = nAgt.indexOf('CriOS')) != -1) {
                //Chrome on iPad spoofing Safari...correct it.
                browser = 'Chrome';
                version = nAgt.substring(verOffset + 6);//should get the criOS ver.
            }

Haven't been able to test (otherwise I would have improved his answer) it to make sure since my iPad is at home and I'm at work, but I thought I'd put it out there.

The kernel might be the operating system or it might be a part of the operating system. In Linux, the kernel is loaded and executed first. Then it starts up other bits of the OS (like init) to make the system useful.

This is especially true in a micro-kernel environment. The kernel has minimal functionality. Everything else, like file systems and TCP/IP, run as a user process.

The correct answer is: There is no such thing as kernel space and user space. The processor instruction set has special permissions to set destructive things like the root of the page table map, or access hardware device memory, etc.

Kernel code has the highest level privileges, and user code the lowest. This prevents user code from crashing the system, modifying other programs, etc.

Generally kernel code is kept under a different memory map than user code (just as user spaces are kept in different memory maps than each other). This is where the "kernel space" and "user space" terms come from. But that is not a hard and fast rule. For example, since the x86 indirectly requires its interrupt/trap handlers to be mapped at all times, part (or some OSes all) of the kernel must be mapped into user space. Again, this does not mean that such code has user privileges.

Why is the kernel/user divide necessary? Some designers disagree that it is, in fact, necessary. Microkernel architecture is based on the idea that the highest privileged sections of code should be as small as possible, with all significant operations done in user privileged code. You would need to study why this might be a good idea, it is not a simple concept (and is famous for both having advantages and drawbacks).

An interrupt is a hardware-generated change-of-flow within the system. An interrupt handler is summoned to deal with the cause of the interrupt; control is then returned to the interrupted context and instruction. A trap is a software-generated interrupt. An interrupt can be used to signal the completion of an I/O to obviate the need for device polling. A trap can be used to call operating system routines or to catch arithmetic errors.

Simple Import os package and run below command.

import os
os.system("python test.py")

The "lsb_release" command provides certain Linux Standard Base and distribution-specific information. So using the below command we can get Operating system name and operating system version.

"lsb_release -a"

Assuming the application you are attempting to run in the background is CLI based, you can try calling the scheduled jobs using Hidden Start

Also see: http://www.howtogeek.com/howto/windows/hide-flashing-command-line-and-batch-file-windows-on-startup/

Besides global memory, threads also share a number of other attributes (i.e., these attributes are global to a process, rather than specific to a thread). These attributes include the following:

• process ID and parent process ID;
• process group ID and session ID;
• controlling terminal;
• process credentials (user and group IDs);
• open file descriptors;
• record locks created using fcntl();
• signal dispositions;
• file system–related information: umask, current working directory, and root directory;
• interval timers (setitimer()) and POSIX timers (timer_create());
• System V semaphore undo (semadj) values (Section 47.8);
• resource limits;
• CPU time consumed (as returned by times());
• resources consumed (as returned by getrusage()); and
• nice value (set by setpriority() and nice()).

Among the attributes that are distinct for each thread are the following:

• thread ID (Section 29.5);
• signal mask;
• thread-specific data (Section 31.3);
• alternate signal stack (sigaltstack());
• the errno variable;
• floating-point environment (see fenv(3));
• realtime scheduling policy and priority (Sections 35.2 and 35.3);
• CPU affinity (Linux-specific, described in Section 35.4);
• capabilities (Linux-specific, described in Chapter 39); and
• stack (local variables and function call linkage information).

Excerpt From: The Linux Programming Interface: A Linux and UNIX System Programming Handbook , Michael Kerrisk, page 619

As an addition about the core of Mac OS X, Finder had not been written in Objective-C prior to Snow Leopard. In Snow Leopard it was written in Cocoa, Objective-C

The difference between an operating system and a kernel:

The kernel is a part of an operating system. The operating system is the software package that communicates directly to the hardware and our application. The kernel is the lowest level of the operating system. The kernel is the main part of the operating system and is responsible for translating the command into something that can be understood by the computer. The main functions of the kernel are:

1. memory management
2. network management
3. device driver
4. file management
5. process management

@ECHO OFF
SETLOCAL ENABLEDELAYEDEXPANSION
SET /a pid=1600
FOR /f "skip=3delims=" %%a IN ('tasklist') DO (
 SET "found=%%a"
 SET /a foundpid=!found:~26,8!
 IF %pid%==!foundpid! echo found %pid%=!found:~0,24%!
)

GOTO :EOF

...set PID to suit your circumstance.

Multitasking:- It handling a number of tasks or jobs simultaneously. In that case user can interact with the system.

Multiprogramming:- It handling a several programs at the same time & it cannot interact with the system, every thing is decided by the OS(Operating System).

You can use sys.platform:

from sys import platform
if platform == "linux" or platform == "linux2":
    # linux
elif platform == "darwin":
    # OS X
elif platform == "win32":
    # Windows...

sys.platform has finer granularity than sys.name.

For the valid values, consult the documentation.

See also the answer to “What OS am I running on?”

There is a library for this purpose: https://github.com/bestiejs/platform.js#readme

Then you can use it this way

// example 1
platform.os; // 'Windows Server 2008 R2 / 7 x64'

// example 2 on an iPad
platform.os; // 'iOS 5.0'

// you can also access on the browser and some other properties
platform.name; // 'Safari'
platform.version; // '5.1'
platform.product; // 'iPad'
platform.manufacturer; // 'Apple'
platform.layout; // 'WebKit'

// or use the description to put all together
platform.description; // 'Safari 5.1 on Apple iPad (iOS 5.0)'

To explain more with respect to concurrent programming

1. A process has a self-contained execution environment. A process generally has a complete, private set of basic run-time resources; in particular, each process has its own memory space.

2. Threads exist within a process — every process has at least one. Threads share the process's resources, including memory and open files. This makes for efficient, but potentially problematic, communication.

An example keeping the average person in mind:

On your computer, open Microsoft Word and a web browser. We call these two processes.

In Microsoft Word, you type something and it gets automatically saved. Now, you have observed editing and saving happens in parallel - editing on one thread and saving on the other thread.

As many folks here have mentioned, a mutex is used to protect a critical piece of code (AKA critical section.) You will acquire the mutex (lock), enter critical section, and release mutex (unlock) all in the same thread.

While using a semaphore, you can make a thread wait on a semaphore (say thread A), until another thread (say thread B)completes whatever task, and then sets the Semaphore for thread A to stop the wait, and continue its task.

There is also another solution to the problem by implementing a layer-list that will act as the background for the LinearLayoout.

Add background_with_shadow.xml file to res/drawable. Containing:

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
    <item >
        <shape 
            android:shape="rectangle">
        <solid android:color="@android:color/darker_gray" />
        <corners android:radius="5dp"/>
        </shape>
    </item>
    <item android:right="1dp" android:left="1dp" android:bottom="2dp">
        <shape 
            android:shape="rectangle">
        <solid android:color="@android:color/white"/>
        <corners android:radius="5dp"/>
        </shape>
    </item>
</layer-list>

Then add the the layer-list as background in your LinearLayout.

<LinearLayout
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:background="@drawable/background_with_shadow"/>

there are some mistakes in your code - the first: you havn't closed you p-tag:

<a href="http//www.google.com"><p style="text-align:center">Search</p></a>

next: p stands for 'paragraph' and is a block-element (so it's causing a line-break). what you wanted to use there is a span, wich is just an inline-element for formatting:

<a href="http//www.google.com"><span style="text-align:center">Search</span></a>

but if you just want to add a style to your link, why don't you set the style for that link directly:

<a href="http//www.google.com" style="text-align:center">Search</a>

in the end, this would at least be correct html, but still not exactly what you want, because text-align:center centers the text in that element, so you would have to set that for the element that contains this links (this piece of html isn't posted, so i can't correct you, but i hope you understand) - to show this, i'll use a simple div:

<div style="text-align:center">    
  <a href="http//www.google.com">Search</a>
  <!-- more links here -->
</div>

EDIT: some more additions to your question:

• p is not a 'function', but you're right, this is causing the problem (because it's a block-element)
• what you're trying to use is css - it's just inline instead of being placed in a seperate file, but you aren't doing 'just HTML' here

Try this:

<?php 
/*
Template Name: [contact us]

*/
get_header();
echo do_shortcode('[CONTACT-US-FORM]'); 
?>

The problem with all presented answers it complete lack of taking triggers (and probably other side effects) into account. Solution like

INSERT OR IGNORE ...
UPDATE ...

leads to both triggers executed (for insert and then for update) when row does not exist.

Proper solution is

UPDATE OR IGNORE ...
INSERT OR IGNORE ...

in that case only one statement is executed (when row exists or not).

SELECT  name
FROM    orders,company
WHERE   orderID = 1
        AND companyID IN (attachedCompanyIDs)

attachedCompanyIDs is a scalar value which is cast into INT (type of companyID).

The cast only returns numbers up to the first non-digit (a comma in your case).

Thus,

companyID IN ('1,2,3') = companyID IN (CAST('1,2,3' AS INT)) = companyID IN (1)

In PostgreSQL, you could cast the string into array (or store it as an array in the first place):

SELECT  name
FROM    orders
JOIN    company
ON      companyID = ANY (('{' | attachedCompanyIDs | '}')::INT[])
WHERE   orderID = 1

and this would even use an index on companyID.

Unfortunately, this does not work in MySQL since the latter does not support arrays.

You may find this article interesting (see #2):

• 10 things in MySQL (that won’t work as expected)

Update:

If there is some reasonable limit on the number of values in the comma separated lists (say, no more than 5), so you can try to use this query:

SELECT  name
FROM    orders
CROSS JOIN
        (
        SELECT  1 AS pos
        UNION ALL
        SELECT  2 AS pos
        UNION ALL
        SELECT  3 AS pos
        UNION ALL
        SELECT  4 AS pos
        UNION ALL
        SELECT  5 AS pos
        ) q
JOIN    company
ON      companyID = CAST(NULLIF(SUBSTRING_INDEX(attachedCompanyIDs, ',', -pos), SUBSTRING_INDEX(attachedCompanyIDs, ',', 1 - pos)) AS UNSIGNED)

You can have both formats as an argument to the function date():

date("d-m-Y H:i:s")

Check the manual for more info : http://php.net/manual/en/function.date.php

As pointed out by @ThomasVdBerge to display minutes you need the 'i' character

It seems the problem is you send the form request to welcome/do_upload, and call the Welcome::do_upload() method in another one by $this->do_upload().

Hence when you call the $this->do_upload(); within your second method, the $_FILES array would be empty.

And that's why var_dump($data['upload_data']); returns NULL.

If you want to upload the file from welcome/second_method, send the form request to the welcome/second_method where you call $this->do_upload();.

Then change the form helper function (within the View) as follows¹:

// Change the 'second_method' to your method name
echo form_open_multipart('welcome/second_method');

File Uploading with CodeIgniter

CodeIgniter has documented the Uploading process very well, by using the File Uploading library.

You could take a look at the sample code in the user guide; And also, in order to get a better understanding of the uploading configs, Check the Config items Explanation section at the end of the manual page.

Also there are couple of articles/samples about the file uploading in CodeIgniter, you might want to consider:

• http://code.tutsplus.com/tutorials/how-to-upload-files-with-codeigniter-and-ajax--net-21684
• http://runnable.com/UhIc93EfFJEMAADX/how-to-upload-file-in-codeigniter
• http://jamshidhashimi.com/image-upload-with-codeigniter-2/
• http://code.tutsplus.com/tutorials/how-to-upload-files-with-codeigniter-and-ajax--net-21684
• http://hashem.ir/CodeIgniter/libraries/file_uploading.html (CodeIgniter 3.0-dev User Guide)

Just as a side-note: Make sure that you've loaded the url and form helper functions before using the CodeIgniter sample code:

// Load the helper files within the Controller
$this->load->helper('form');
$this->load->helper('url');

_{1. The form must be "multipart" type for file uploading. Hence you should use form_open_multipart() helper function which returns:
<form method="post" action="controller/method" enctype="multipart/form-data" />}

Here's a little cmd script you can copy-n-paste into a file named something like where.cmd:

@echo off
rem - search for the given file in the directories specified by the path, and display the first match
rem
rem    The main ideas for this script were taken from Raymond Chen's blog:
rem
rem         http://blogs.msdn.com/b/oldnewthing/archive/2005/01/20/357225.asp
rem
rem
rem - it'll be nice to at some point extend this so it won't stop on the first match. That'll
rem     help diagnose situations with a conflict of some sort.
rem

setlocal

rem - search the current directory as well as those in the path
set PATHLIST=.;%PATH%
set EXTLIST=%PATHEXT%

if not "%EXTLIST%" == "" goto :extlist_ok
set EXTLIST=.COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH
:extlist_ok

rem - first look for the file as given (not adding extensions)
for %%i in (%1) do if NOT "%%~$PATHLIST:i"=="" echo %%~$PATHLIST:i

rem - now look for the file adding extensions from the EXTLIST
for %%e in (%EXTLIST%) do @for %%i in (%1%%e) do if NOT "%%~$PATHLIST:i"=="" echo %%~$PATHLIST:i

You can also create a database named 'mydatabasename' and then try restoring it again.

Create a new database using MySQL CLI:

mysql -u[username] -p[password]
CREATE DATABASE mydatabasename;

Then try to restore your database:

mysql -u[username] -p[password] mydatabase<mydatabase.sql;

you can use this project to play any you tube video , in your android app . Now for other video , or Video id ... you can do this https://gdata.youtube.com/feeds/api/users/eminemvevo/uploads/ where eminemvevo = channel .

after finding , video id , you can put that id in cueVideo("video_id")

src -> com -> examples -> youtubeapidemo -> PlayerViewDemoActivity

  @Override
  public void onInitializationSuccess(YouTubePlayer.Provider provider, YouTubePlayer player , boolean wasRestored) {
    if (!wasRestored) {
      player.cueVideo("wKJ9KzGQq0w");
    }
  }

And specially for reading that video_id in a better way open this , and it as a xml[1st_file] file in your desktop after it create a new Xml file in your project or upload that[1st_file] saved file in your project , and right_click in it , and open it with xml_editor file , here you will find the video id of the particular video .

If none of the other answers are satisfactory, you could always just create an empty row and style it with CSS appropriately to be transparent.

The method arrayList.size() returns the number of items in the list - so if the index is greater than or equal to the size(), it doesn't exist.

if(index >= myList.size()){
  //index not exists
}else{
 // index exists
}

You should implement OnEditorActionListener for your EditView

public void performClickOnDone(EditView editView, final View button){
    textView.setOnEditorActionListener(new OnEditorActionListener() {

        @Override
        public boolean onEditorAction(EditView v, int actionId, KeyEvent event) {
            hideKeyboard();
            button.requestFocus();
            button.performClick();
            return true;
        }
    });

And you hide keyboard by:

public void hideKeybord(View view) {
    inputMethodManager.hideSoftInputFromWindow(view.getWindowToken(),
                                  InputMethodManager.RESULT_UNCHANGED_SHOWN);
}

You should also fire keyboard hiding in your button using onClickListener

Now clicking 'Done' on virtual keyboard and button will do the same - hide keyboard and perform click action.

On the server.. In our environment, we're running Apache2 on Windows Server 2003.
Suppose Apache is serving our repository from C:\repo\MyProject

The actual repository is in C:\repo\MyProject\db

and the configuration is in C:\repo\MyProject\conf

So the passwords are in: C:\repo\MyProject.htaccess

They're encrypted, a tool similar to this: http://tools.dynamicdrive.com/password/

$("#item").removeClass();

Calling removeClass with no parameters will remove all of the item's classes.

You can also use (but is not necessarily recommended, the correct way is the one above):

$("#item").removeAttr('class');
$("#item").attr('class', '');
$('#item')[0].className = '';

If you didn't have jQuery, then this would be pretty much your only option:

document.getElementById('item').className = '';

This should help you.

from sklearn.feature_extraction.text import TfidfVectorizer
from sklearn.metrics.pairwise import cosine_similarity  

tfidf_vectorizer = TfidfVectorizer()
tfidf_matrix = tfidf_vectorizer.fit_transform(train_set)
print tfidf_matrix
cosine = cosine_similarity(tfidf_matrix[length-1], tfidf_matrix)
print cosine

and output will be:

[[ 0.34949812  0.81649658  1.        ]]

I found this to be helpful:

http://dan.clarke.name/2011/07/enum-in-java-with-int-conversion/

public enum Difficulty
{
    EASY(0),
    MEDIUM(1),
    HARD(2);

    /**
    * Value for this difficulty
    */
    public final int Value;

    private Difficulty(int value)
    {
        Value = value;
    }

    // Mapping difficulty to difficulty id
    private static final Map<Integer, Difficulty> _map = new HashMap<Integer, Difficulty>();
    static
    {
        for (Difficulty difficulty : Difficulty.values())
            _map.put(difficulty.Value, difficulty);
    }

    /**
    * Get difficulty from value
    * @param value Value
    * @return Difficulty
    */
    public static Difficulty from(int value)
    {
        return _map.get(value);
    }
}

The free and open-source program called cabextract will list and extract the contents of not just .cab-files, but Macrovision's archives too:

% cabextract /tmp/QLWREL.EXE
Extracting cabinet: /tmp/QLWREL.EXE
  extracting ikernel.dll
  extracting IsProBENT.tlb
  ....
  extracting IScript.dll
  extracting iKernel.rgs

All done, no errors.

This is my favorite method for being easy to read:

Dir.glob("*/*.txt") do |my_text_file|
  puts "working on: #{my_text_file}..."
end

And you can even extend this to work on all files in subdirs:

Dir.glob("**/*.txt") do |my_text_file| # note one extra "*"
  puts "working on: #{my_text_file}..."
end

Date()

With this you call a function called Date(). It doesn't accept any arguments and returns a string representing the current date and time.

new Date()

With this you're creating a new instance of Date.

You can use only the following constructors:

new Date() // current date and time
new Date(milliseconds) //milliseconds since 1970/01/01
new Date(dateString)
new Date(year, month, day, hours, minutes, seconds, milliseconds)

So, use 2010-08-17 12:09:36 as parameter to constructor is not allowed.

See w3schools.

EDIT: new Date(dateString) uses one of these formats:

• "October 13, 1975 11:13:00"
• "October 13, 1975 11:13"
• "October 13, 1975"

Get Network and Local Printer List in ASP.NET

This method uses the Windows Management Instrumentation or the WMI interface. It’s a technology used to get information about various systems (hardware) running on a Windows Operating System.

private void GetAllPrinterList()
        {
            ManagementScope objScope = new ManagementScope(ManagementPath.DefaultPath); //For the local Access
            objScope.Connect();

            SelectQuery selectQuery = new SelectQuery();
            selectQuery.QueryString = "Select * from win32_Printer";
            ManagementObjectSearcher MOS = new ManagementObjectSearcher(objScope, selectQuery);
            ManagementObjectCollection MOC = MOS.Get();
            foreach (ManagementObject mo in MOC)
            {
                lstPrinterList.Items.Add(mo["Name"].ToString());
            }
        }

Click here to download source and application demo

Demo of application which listed network and local printer

This will be different for each OS, based on the information at https://code.visualstudio.com/docs/customization/keybindings

Go Back: workbench.action.navigateBack Go Forward: workbench.action.navigateForward

Linux Go Back: Ctrl+Alt+-
Go Forward: Ctrl+Shift+-

OSX ^- / ^?-

Windows Alt+ ? / ?

If you facing grant permission access denied problem, you can try mysql_upgrade to fix the problem:

/usr/bin/mysql_upgrade -u root -p

Login as root:

mysql -u root -p

Run this commands:

mysql> GRANT ALL PRIVILEGES ON *.* TO 'root'@'localhost';
mysql> FLUSH PRIVILEGES;

You could use a list comprehension or a generator expression instead:

', '.join([str(x) for x in list])  # list comprehension
', '.join(str(x) for x in list)    # generator expression

You don't mention what language you want to track these in, but I found two for javascript:

http://www.cambiaresearch.com/c4/702b8cd1-e5b0-42e6-83ac-25f0306e3e25/Javascript-Char-Codes-Key-Codes.aspx

use below command while installing packages

 sudo npm install --unsafe-perm=true --allow-root

On a MAC, you need to use nm *.o | c++filt, as there is no -C option in nm.

You've already discovered the simplest way to specify a shallow clone in Git-SVN, by specifying the SVN revision number that you want to start your clone at ( -r$REV:HEAD).

For example: git svn clone -s -r1450:HEAD some/svn/repo

Git's data structure is based on pointers in a directed acyclic graph (DAG), which makes it trivial to walk back n commits. But in SVN ( and therefore in Git-SVN) you will have to find the revision number yourself.

If you wish to run one script and only one script, you can make it that users default shell.

echo "/usr/bin/uptime" >> /etc/shells
vim /etc/passwd  
  * username:x:uid:grp:message:homedir:/usr/bin/uptime

can have interesting effects :) ( its not secure tho, so don't trust it too much. nothing like setting your default shell to be a script that wipes your drive. ... although, .. I can imagine a scenario where that could be amazingly useful )

Updated for swift 3:

// function defination:

@IBAction func showAlertDialog(_ sender: UIButton) {
        // Declare Alert
        let dialogMessage = UIAlertController(title: "Confirm", message: "Are you sure you want to Logout?", preferredStyle: .alert)

        // Create OK button with action handler
        let ok = UIAlertAction(title: "OK", style: .default, handler: { (action) -> Void in
             print("Ok button click...")
             self.logoutFun()
        })

        // Create Cancel button with action handlder
        let cancel = UIAlertAction(title: "Cancel", style: .cancel) { (action) -> Void in
            print("Cancel button click...")
        }

        //Add OK and Cancel button to dialog message
        dialogMessage.addAction(ok)
        dialogMessage.addAction(cancel)

        // Present dialog message to user
        self.present(dialogMessage, animated: true, completion: nil)
    }

// logoutFun() function definaiton :

func logoutFun()
{
    print("Logout Successfully...!")
}

Another option is

if (myString?.trim()) {
  ...
}

In simple words, strace traces all system calls issued by a program along with their return codes. Think things such as file/socket operations and a lot more obscure ones.

It is most useful if you have some working knowledge of C since here system calls would more accurately stand for standard C library calls.

Let's say your program is /usr/local/bin/cough. Simply use:

strace /usr/local/bin/cough <any required argument for cough here>

or

strace -o <out_file> /usr/local/bin/cough <any required argument for cough here>

to write into 'out_file'.

All strace output will go to stderr (beware, the sheer volume of it often asks for a redirection to a file). In the simplest cases, your program will abort with an error and you'll be able to see what where its last interactions with the OS in strace output.

More information should be available with:

man strace

The best and the easiest way to do it, in IntelliJ Idea in the window “Maven Project”, and just don’t click on the test button. I hope, I helped you. Have a good day :)

The first line of a paragraph is indented by default, thus whether or not you have \indent there won't make a difference. \indent and \noindent can be used to override default behavior. You can see this by replacing your line with the following:

Now we are engaged in a great civil war.\\
\indent this is indented\\
this isn't indented


\noindent override default indentation (not indented)\\
asdf 

I came across this post in search for the dockerhub repo URL when creating a dockerhub kubernetes secret.. figured id share the URL is used with success, hope that's ok.

Live Current: https://index.docker.io/v2/

Dead Orginal: https://index.docker.io/v1/

I would write the code like this:

def search_book(request):
    form = SearchForm(request.POST or None)
    if request.method == "POST" and form.is_valid():
        stitle = form.cleaned_data['title']
        sauthor = form.cleaned_data['author']
        scategory = form.cleaned_data['category']
        return HttpResponseRedirect('/thanks/')
    return render_to_response("books/create.html", {
        "form": form,
    }, context_instance=RequestContext(request))

Pretty much like the documentation.

check below link to convert JSON data to standard HTML table in the simplest and fastest way.

http://crunchify.com/crunchifyjsontohtml-js-json-to-html-table-converter-script/

I've not found anything in the API, but one thing you could do is attach an event handler to the standard paginator and detect if it has changed:

$('.dataTables_length select').live('change', function(){
       alert(this.value);
    });

With REGEXP_SUBSTR is as simple as:

SELECT REGEXP_SUBSTR(t.column_one, '[^ ]+', 1, 1) col_one,
       REGEXP_SUBSTR(t.column_one, '[^ ]+', 1, 2) col_two
FROM YOUR_TABLE t;

You can just get the individual time components and calculate the total. You seem to be expecting Moment to already have this feature neatly packaged up for you, but it doesn't. I doubt it's something that people have a need for very often.

Example:

var m = moment();_x000D_
_x000D_
var ms = m.milliseconds() + 1000 * (m.seconds() + 60 * (m.minutes() + 60 * m.hours()));_x000D_
_x000D_
console.log(ms);

<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.18.1/moment.min.js"></script>

All you need to do is pass the JspWriter object into your method as a parameter i.e.

void someOutput(JspWriter stream)

Then call it via:

<% someOutput(out) %>

The writer object is a local variable inside _jspService so you need to pass it into your utility method. The same would apply for all the other built in references (e.g. request, response, session).

A great way to see whats going on is to use Tomcat as your server and drill down into the 'work' directory for the '.java' file generated from your 'jsp' page. Alternatively in weblogic you can use the 'weblogic.jspc' page compiler to view the Java that will be generated when the page is requested.

If anyone else runs into a similar issue with fopen file permissions error, but is wise enough not to blindly chmod 777 here is my suggestion.

Check the command you are using for permissions that apache needs:

fopen('filepath/filename.pdf', 'r');

The 'r' means open for read only, and if you aren't editing the file, this is what you should have it set as. This means apache/www-data needs at least read permission on that file, which if the file is created through laravel it will have read permission already.

If for any reason you have to write to the file:

fopen('filepath/filename.pdf', 'r+');

Then make sure apache also has permissions to write to the file.

http://php.net/manual/en/function.fopen.php

You can run Rundll32.exe for IE Options control panel applet and achieve following tasks.

Deletes ALL History - RunDll32.exe InetCpl.cpl,ClearMyTracksByProcess 255

Deletes History Only - RunDll32.exe InetCpl.cpl,ClearMyTracksByProcess 1

Deletes Cookies Only - RunDll32.exe InetCpl.cpl,ClearMyTracksByProcess 2

Deletes Temporary Internet Files Only - RunDll32.exe InetCpl.cpl,ClearMyTracksByProcess 8

Deletes Form Data Only - RunDll32.exe InetCpl.cpl,ClearMyTracksByProcess 16

Deletes Password History Only - RunDll32.exe InetCpl.cpl,ClearMyTracksByProcess 32

Here are three methods using windows powershell and/or powershell core, listed from fastest to slowest. You can assign it to a variable of your choosing.

$ipAddress = (Get-NetIPAddress | Where-Object {$_.AddressState -eq "Preferred" -and $_.ValidLifetime -lt "24:00:00"}).IPAddress

$ipAddress = (Test-Connection -ComputerName (hostname) -Count 1 | Select -ExpandProperty IPv4Address).IPAddressToString

$ipAddress = (Get-NetIPConfiguration | Where-Object {$_.IPv4DefaultGateway -ne $null -and $_.NetAdapter.status -ne "Disconnected"}).IPv4Address.IPAddress

If you're wondering why this optimization was added to range.__contains__, and why it wasn't added to xrange.__contains__ in 2.7:

First, as Ashwini Chaudhary discovered, issue 1766304 was opened explicitly to optimize [x]range.__contains__. A patch for this was accepted and checked in for 3.2, but not backported to 2.7 because "xrange has behaved like this for such a long time that I don't see what it buys us to commit the patch this late." (2.7 was nearly out at that point.)

Meanwhile:

Originally, xrange was a not-quite-sequence object. As the 3.1 docs say:

Range objects have very little behavior: they only support indexing, iteration, and the len function.

This wasn't quite true; an xrange object actually supported a few other things that come automatically with indexing and len,^* including __contains__ (via linear search). But nobody thought it was worth making them full sequences at the time.

Then, as part of implementing the Abstract Base Classes PEP, it was important to figure out which builtin types should be marked as implementing which ABCs, and xrange/range claimed to implement collections.Sequence, even though it still only handled the same "very little behavior". Nobody noticed that problem until issue 9213. The patch for that issue not only added index and count to 3.2's range, it also re-worked the optimized __contains__ (which shares the same math with index, and is directly used by count).^** This change went in for 3.2 as well, and was not backported to 2.x, because "it's a bugfix that adds new methods". (At this point, 2.7 was already past rc status.)

So, there were two chances to get this optimization backported to 2.7, but they were both rejected.

_{* In fact, you even get iteration for free with indexing alone, but in 2.3 xrange objects got a custom iterator.}

_{** The first version actually reimplemented it, and got the details wrong—e.g., it would give you MyIntSubclass(2) in range(5) == False. But Daniel Stutzbach's updated version of the patch restored most of the previous code, including the fallback to the generic, slow _PySequence_IterSearch that pre-3.2 range.__contains__ was implicitly using when the optimization doesn't apply.}

One way to speed things up is to explicitly perform multiple inserts or copy's within a transaction (say 1000). Postgres's default behavior is to commit after each statement, so by batching the commits, you can avoid some overhead. As the guide in Daniel's answer says, you may have to disable autocommit for this to work. Also note the comment at the bottom that suggests increasing the size of the wal_buffers to 16 MB may also help.

Maybe wrong path..? Check your .classpath file.

default_data['item3'] = 3

Easy as py.

Another possible solution:

default_data.update({'item3': 3})

which is nice if you want to insert multiple items at once.

The issue here is that JSON, as a format, is generally parsed in full and then handled in-memory, which for such a large amount of data is clearly problematic.

The solution to this is to work with the data as a stream - reading part of the file, working with it, and then repeating.

The best option appears to be using something like ijson - a module that will work with JSON as a stream, rather than as a block file.

Edit: Also worth a look - kashif's comment about json-streamer and Henrik Heino's comment about bigjson.

You normally use a tool like pip to install wheels. Leave it to the tool to discover and download the file if this is for a project hosted on PyPI.

For this to work, you do need to install the wheel package:

pip install wheel

You can then tell pip to install the project (and it'll download the wheel if available), or the wheel file directly:

pip install project_name  # discover, download and install
pip install wheel_file.whl  # directly install the wheel

The wheel module, once installed, also is runnable from the command line, you can use this to install already-downloaded wheels:

python -m wheel install wheel_file.whl

Also see the wheel project documentation.

As described here for a post request :

var http = require('http');

var options = {
  host: 'www.host.com',
  path: '/',
  port: '80',
  method: 'POST'
};

callback = function(response) {
  var str = ''
  response.on('data', function (chunk) {
    str += chunk;
  });

  response.on('end', function () {
    console.log(str);
  });
}

var req = http.request(options, callback);
//This is the data we are posting, it needs to be a string or a buffer
req.write("data");
req.end();

You can also have a look at the method findText(const QString & text) from QComboBox; it returns the index of the element which contains the given text, (-1 if not found). The advantage of using this method is that you don't need to set the second parameter when you add an item.

Here is a little example :

/* Create the comboBox */
QComboBox   *_comboBox = new QComboBox;

/* Create the ComboBox elements list (here we use QString) */
QList<QString> stringsList;
stringsList.append("Text1");
stringsList.append("Text3");
stringsList.append("Text4");
stringsList.append("Text2");
stringsList.append("Text5");

/* Populate the comboBox */
_comboBox->addItems(stringsList);

/* Create the label */
QLabel *label = new QLabel;

/* Search for "Text2" text */
int index = _comboBox->findText("Text2");
if( index == -1 )
    label->setText("Text2 not found !");
else
    label->setText(QString("Text2's index is ")
                   .append(QString::number(_comboBox->findText("Text2"))));

/* setup layout */
QVBoxLayout *layout = new QVBoxLayout(this);
layout->addWidget(_comboBox);
layout->addWidget(label);

For future readers.

I wanted specific control over this issue, so this is what I did:

From a fragment or activity, hide your other views (that aren't needed while the keyboard is up), then restore them to solve this problem:

rootView.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
     @Override
     public void onGlobalLayout() {
        Rect r = new Rect();
        rootView.getWindowVisibleDisplayFrame(r);
        int heightDiff = rootView.getRootView().getHeight() - (r.bottom - r.top);

        if (heightDiff > 100) { // if more than 100 pixels, its probably a keyboard...
           //ok now we know the keyboard is up...
           view_one.setVisibility(View.GONE);
           view_two.setVisibility(View.GONE);

        } else {
           //ok now we know the keyboard is down...
           view_one.setVisibility(View.VISIBLE);
           view_two.setVisibility(View.VISIBLE);       
        }
     }
});

Solution to allow Apache 2 to host websites outside of htdocs:

Underneath the "DocumentRoot" directive in httpd.conf, you should see a directory block. Replace this directory block with:

<Directory />
    Options FollowSymLinks
    AllowOverride All
    Allow from all
</Directory> 

REMEMBER NOT TO USE THIS CONFIGURATION IN A REAL ENVIRONMENT

This is mainly for future readers. As the question (at least the title) focuses on "connecting to sql server database from node js", I would like to chip in about "mssql" node module.

At this moment, we have a stable version of Microsoft SQL Server driver for NodeJs ("msnodesql") available here: https://www.npmjs.com/package/msnodesql. While it does a great job of native integration to Microsoft SQL Server database (than any other node module), there are couple of things to note about.

"msnodesql" require a few pre-requisites (like python, VC++, SQL native client etc.) to be installed on the host machine. That makes your "node" app "Windows" dependent. If you are fine with "Windows" based deployment, working with "msnodesql" is the best.

On the other hand, there is another module called "mssql" (available here https://www.npmjs.com/package/mssql) which can work with "tedious" or "msnodesql" based on configuration. While this module may not be as comprehensive as "msnodesql", it pretty much solves most of the needs.

If you would like to start with "mssql", I came across a simple and straight forward video, which explains about connecting to Microsoft SQL Server database using NodeJs here: https://www.youtube.com/watch?v=MLcXfRH1YzE

Source code for the above video is available here: http://techcbt.com/Post/341/Node-js-basic-programming-tutorials-videos/how-to-connect-to-microsoft-sql-server-using-node-js

Just in case, if the above links are not working, I am including the source code here:

var sql = require("mssql");_x000D_
_x000D_
var dbConfig = {_x000D_
    server: "localhost\\SQL2K14",_x000D_
    database: "SampleDb",_x000D_
    user: "sa",_x000D_
    password: "sql2014",_x000D_
    port: 1433_x000D_
};_x000D_
_x000D_
function getEmp() {_x000D_
    var conn = new sql.Connection(dbConfig);_x000D_
    _x000D_
    conn.connect().then(function () {_x000D_
        var req = new sql.Request(conn);_x000D_
        req.query("SELECT * FROM emp").then(function (recordset) {_x000D_
            console.log(recordset);_x000D_
            conn.close();_x000D_
        })_x000D_
        .catch(function (err) {_x000D_
            console.log(err);_x000D_
            conn.close();_x000D_
        });        _x000D_
    })_x000D_
    .catch(function (err) {_x000D_
        console.log(err);_x000D_
    });_x000D_
_x000D_
    //--> another way_x000D_
    //var req = new sql.Request(conn);_x000D_
    //conn.connect(function (err) {_x000D_
    //    if (err) {_x000D_
    //        console.log(err);_x000D_
    //        return;_x000D_
    //    }_x000D_
    //    req.query("SELECT * FROM emp", function (err, recordset) {_x000D_
    //        if (err) {_x000D_
    //            console.log(err);_x000D_
    //        }_x000D_
    //        else { _x000D_
    //            console.log(recordset);_x000D_
    //        }_x000D_
    //        conn.close();_x000D_
    //    });_x000D_
    //});_x000D_
_x000D_
}_x000D_
_x000D_
getEmp();

The above code is pretty self explanatory. We define the db connection parameters (in "dbConfig" JS object) and then use "Connection" object to connect to SQL Server. In order to execute a "SELECT" statement, in this case, it uses "Request" object which internally works with "Connection" object. The code explains both flavors of using "promise" and "callback" based executions.

The above source code explains only about connecting to sql server database and executing a SELECT query. You can easily take it to the next level by following documentation of "mssql" node available at: https://www.npmjs.com/package/mssql

UPDATE: There is a new video which does CRUD operations using pure Node.js REST standard (with Microsoft SQL Server) here: https://www.youtube.com/watch?v=xT2AvjQ7q9E. It is a fantastic video which explains everything from scratch (it has got heck a lot of code and it will not be that pleasing to explain/copy the entire code here)

1. fork() - creates a new child process, which is a complete copy of the parent process. Child and parent processes use different virtual address spaces, which is initially populated by the same memory pages. Then, as both processes are executed, the virtual address spaces begin to differ more and more, because the operating system performs a lazy copying of memory pages that are being written by either of these two processes and assigns an independent copies of the modified pages of memory for each process. This technique is called Copy-On-Write (COW).
2. vfork() - creates a new child process, which is a "quick" copy of the parent process. In contrast to the system call fork(), child and parent processes share the same virtual address space. NOTE! Using the same virtual address space, both the parent and child use the same stack, the stack pointer and the instruction pointer, as in the case of the classic fork()! To prevent unwanted interference between parent and child, which use the same stack, execution of the parent process is frozen until the child will call either exec() (create a new virtual address space and a transition to a different stack) or _exit() (termination of the process execution). vfork() is the optimization of fork() for "fork-and-exec" model. It can be performed 4-5 times faster than the fork(), because unlike the fork() (even with COW kept in the mind), implementation of vfork() system call does not include the creation of a new address space (the allocation and setting up of new page directories).
3. clone() - creates a new child process. Various parameters of this system call, specify which parts of the parent process must be copied into the child process and which parts will be shared between them. As a result, this system call can be used to create all kinds of execution entities, starting from threads and finishing by completely independent processes. In fact, clone() system call is the base which is used for the implementation of pthread_create() and all the family of the fork() system calls.
4. exec() - resets all the memory of the process, loads and parses specified executable binary, sets up new stack and passes control to the entry point of the loaded executable. This system call never return control to the caller and serves for loading of a new program to the already existing process. This system call with fork() system call together form a classical UNIX process management model called "fork-and-exec".

Ok why the complicated use of libraries and stuff? C++ String objects overload the [] operator, so you can just compare chars.. Like what I just did, because I want to list all files in a directory and ignore invisible files and the .. and . pseudofiles.

while ((ep = readdir(dp)))
{
    string s(ep->d_name);
    if (!(s[0] == '.')) // Omit invisible files and .. or .
        files.push_back(s);
}

It's that simple..

Look no more for IP addresses not being set in the expected header. Just do the following to inspect the whole server variables and figure out which one is suitable for your case:

print_r($_SERVER);

Is some unattended scripts I use the following command:

sh -c "$(curl -fsSL <URL>)"

I recommend to avoid executing scripts directly from URLs. You should be sure the URL is safe and check the content of the script before executing, you can use a SHA256 checksum to validate the file before executing.

for more extendability for large scale apps use oop style with encapsulated fields.

Simple way :-

  class Fruit implements JsonSerializable {

        private $type = 'Apple', $lastEaten = null;

        public function __construct() {
            $this->lastEaten = new DateTime();
        }

        public function jsonSerialize() {
            return [
                'category' => $this->type,
                'EatenTime' => $this->lastEaten->format(DateTime::ISO8601)
            ];
        }
    }

echo json_encode(new Fruit()); //which outputs:

{"category":"Apple","EatenTime":"2013-01-31T11:17:07-0500"}

Real Gson on PHP :-

1. http://jmsyst.com/libs/serializer
2. http://symfony.com/doc/current/components/serializer.html
3. http://framework.zend.com/manual/current/en/modules/zend.serializer.html
4. http://fractal.thephpleague.com/ - serialize only

How I update my deviceToken

First when I login I send the first device token under the user collection and the current logged in user.

After that, I just override onNewToken(token:String) in my FirebaseMessagingService() and just update that value if a new token is generated for that user

class MyFirebaseMessagingService: FirebaseMessagingService() {
    override fun onMessageReceived(p0: RemoteMessage) {
        super.onMessageReceived(p0)
    }

    override fun onNewToken(token: String) {
    super.onNewToken(token)
    val currentUser= FirebaseAuth.getInstance().currentUser?.uid
    if(currentUser != null){
        FirebaseFirestore.getInstance().collection("user").document(currentUser).update("deviceToken",token)
    }
 }
} 

Each time your app opens it will check for a new token, if the user is not yet signed in it will not update the token, if the user is already logged in you can check for a newToken

I landed up on this page when searching for a solution for “Could not open input file” error. Here's my 2 cents for this error.

I faced this same error while because I was using parameters in my php file path like this:

/usr/bin/php -q /home/**/public_html/cron/job.php?id=1234

But I found out that this is not the proper way to do it. The proper way of sending parameters is like this:

/usr/bin/php -q /home/**/public_html/cron/job.php id=1234

Just replace the "?" with a space " ".

<div id='myInputF2'> YES ITS DIV TEXT TO COPY  </div>

<script>

    function myFunctionF2()  {
        str = document.getElementById('myInputF2').innerHTML;
        const el = document.createElement('textarea');
        el.value = str;
        document.body.appendChild(el);
        el.select();
        document.execCommand('copy');
        document.body.removeChild(el);
        alert('Copied the text:' + el.value);
    };
</script>

more info: https://hackernoon.com/copying-text-to-clipboard-with-javascript-df4d4988697f

Try this:

$("#test-element").on("click" ,function() {
    alert("click");
});

The document way of doing it is weird too. That would make sense to me if used for a class selector, but in the case of an id you probably just have useless DOM traversing there. In the case of the id selector, you get that element instantly.

As brb tea says, depends on the database implementation and the algorithm they use: MVCC or Two Phase Locking.

CUBRID (open source RDBMS) explains the idea of this two algorithms:

• Two-phase locking (2PL)

The first one is when the T2 transaction tries to change the A record, it knows that the T1 transaction has already changed the A record and waits until the T1 transaction is completed because the T2 transaction cannot know whether the T1 transaction will be committed or rolled back. This method is called Two-phase locking (2PL).

• Multi-version concurrency control (MVCC)

The other one is to allow each of them, T1 and T2 transactions, to have their own changed versions. Even when the T1 transaction has changed the A record from 1 to 2, the T1 transaction leaves the original value 1 as it is and writes that the T1 transaction version of the A record is 2. Then, the following T2 transaction changes the A record from 1 to 3, not from 2 to 4, and writes that the T2 transaction version of the A record is 3.

When the T1 transaction is rolled back, it does not matter if the 2, the T1 transaction version, is not applied to the A record. After that, if the T2 transaction is committed, the 3, the T2 transaction version, will be applied to the A record. If the T1 transaction is committed prior to the T2 transaction, the A record is changed to 2, and then to 3 at the time of committing the T2 transaction. The final database status is identical to the status of executing each transaction independently, without any impact on other transactions. Therefore, it satisfies the ACID property. This method is called Multi-version concurrency control (MVCC).

The MVCC allows concurrent modifications at the cost of increased overhead in memory (because it has to maintain different versions of the same data) and computation (in REPETEABLE_READ level you can't loose updates so it must check the versions of the data, like Hiberate does with Optimistick Locking).

In 2PL Transaction isolation levels control the following:

• Whether locks are taken when data is read, and what type of locks are requested.

• How long the read locks are held.

• Whether a read operation referencing rows modified by another transaction:

  • Block until the exclusive lock on the row is freed.

  • Retrieve the committed version of the row that existed at the time the statement or transaction started.

  • Read the uncommitted data modification.

Choosing a transaction isolation level does not affect the locks that are acquired to protect data modifications. A transaction always gets an exclusive lock on any data it modifies and holds that lock until the transaction completes, regardless of the isolation level set for that transaction. For read operations, transaction isolation levels primarily define the level of protection from the effects of modifications made by other transactions.

A lower isolation level increases the ability of many users to access data at the same time, but increases the number of concurrency effects, such as dirty reads or lost updates, that users might encounter.

Concrete examples of the relation between locks and isolation levels in SQL Server (use 2PL except on READ_COMMITED with READ_COMMITTED_SNAPSHOT=ON)

• READ_UNCOMMITED: do not issue shared locks to prevent other transactions from modifying data read by the current transaction. READ UNCOMMITTED transactions are also not blocked by exclusive locks that would prevent the current transaction from reading rows that have been modified but not committed by other transactions. [...]

• READ_COMMITED:

  • If READ_COMMITTED_SNAPSHOT is set to OFF (the default): uses shared locks to prevent other transactions from modifying rows while the current transaction is running a read operation. The shared locks also block the statement from reading rows modified by other transactions until the other transaction is completed. [...] Row locks are released before the next row is processed. [...]
  • If READ_COMMITTED_SNAPSHOT is set to ON, the Database Engine uses row versioning to present each statement with a transactionally consistent snapshot of the data as it existed at the start of the statement. Locks are not used to protect the data from updates by other transactions.

• REPETEABLE_READ: Shared locks are placed on all data read by each statement in the transaction and are held until the transaction completes.

• SERIALIZABLE: Range locks are placed in the range of key values that match the search conditions of each statement executed in a transaction. [...] The range locks are held until the transaction completes.

try

<select onchange="location=this.value">_x000D_
    <option value="unit_01.htm">Unit 1</option>_x000D_
    <option value="#5.2" selected >Bookmark 2</option>_x000D_
</select>

In Simple Rails terms:

h remove html tags into number characters so that rendering won't break your html

html_safe sets a boolean in string so that the string is considered as html save

raw It converts to html_safe to string

Here is a list of examples for sending cookies - https://github.com/andriichuk/php-curl-cookbook#cookies

$curlHandler = curl_init();

curl_setopt_array($curlHandler, [
CURLOPT_URL => 'https://httpbin.org/cookies',
CURLOPT_RETURNTRANSFER => true,

CURLOPT_COOKIEFILE  => $cookieFile,
CURLOPT_COOKIE => 'foo=bar;baz=foo',

/**
 * Or set header
 * CURLOPT_HTTPHEADER => [
       'Cookie: foo=bar;baz=foo',
   ]
 */
]);

$response = curl_exec($curlHandler);
curl_close($curlHandler);

echo $response;

There is a new parameter expansion added in bash 4.4 that interprets escape sequences:

${parameter@operator} - E operator

The expansion is a string that is the value of parameter with backslash escape sequences expanded as with the $'…' quoting mechanism.

$ foo='hello\nworld'
$ echo "${foo@E}"
hello
world

You don't have g++ installed, simple way to have all the needed build tools is to install the package build-essential:

sudo apt-get install build-essential

, or just the g++ package:

sudo apt-get install g++

In case anybody is looking for methods to convert from/to C# and SQL Server formats, here goes a simple implementation:

private readonly string[] SqlServerTypes = { "bigint", "binary", "bit",  "char", "date",     "datetime", "datetime2", "datetimeoffset", "decimal", "filestream", "float",  "geography",                              "geometry",                              "hierarchyid",                              "image",  "int", "money",   "nchar",  "ntext",  "numeric", "nvarchar", "real",   "rowversion", "smalldatetime", "smallint", "smallmoney", "sql_variant", "text",   "time",     "timestamp", "tinyint", "uniqueidentifier", "varbinary", "varchar", "xml" };
private readonly string[] CSharpTypes    = { "long",   "byte[]", "bool", "char", "DateTime", "DateTime", "DateTime",  "DateTimeOffset", "decimal", "byte[]",     "double", "Microsoft.SqlServer.Types.SqlGeography", "Microsoft.SqlServer.Types.SqlGeometry", "Microsoft.SqlServer.Types.SqlHierarchyId", "byte[]", "int", "decimal", "string", "string", "decimal", "string",   "Single", "byte[]",     "DateTime",      "short",    "decimal",    "object",      "string", "TimeSpan", "byte[]",    "byte",    "Guid",             "byte[]",    "string",  "string" };

public string ConvertSqlServerFormatToCSharp(string typeName)
{
    var index = Array.IndexOf(SqlServerTypes, typeName);

    return index > -1
        ? CSharpTypes[index]
        : "object";
}

public string ConvertCSharpFormatToSqlServer(string typeName)
{
    var index = Array.IndexOf(CSharpTypes, typeName);

    return index > -1
        ? SqlServerTypes[index]
        : null;
}

Edit: fixed typo

Swift 4 and above

@IBAction func submitAction(sender: UIButton) {

    //declare parameter as a dictionary which contains string as key and value combination. considering inputs are valid

    let parameters = ["id": 13, "name": "jack"]

    //create the url with URL
    let url = URL(string: "www.thisismylink.com/postName.php")! //change the url

    //create the session object
    let session = URLSession.shared

    //now create the URLRequest object using the url object
    var request = URLRequest(url: url)
    request.httpMethod = "POST" //set http method as POST

    do {
        request.httpBody = try JSONSerialization.data(withJSONObject: parameters, options: .prettyPrinted) // pass dictionary to nsdata object and set it as request body
    } catch let error {
        print(error.localizedDescription)
    }

    request.addValue("application/json", forHTTPHeaderField: "Content-Type")
    request.addValue("application/json", forHTTPHeaderField: "Accept")

    //create dataTask using the session object to send data to the server
    let task = session.dataTask(with: request as URLRequest, completionHandler: { data, response, error in

        guard error == nil else {
            return
        }

        guard let data = data else {
            return
        }

        do {
            //create json object from data
            if let json = try JSONSerialization.jsonObject(with: data, options: .mutableContainers) as? [String: Any] {
                print(json)
                // handle json...
            }
        } catch let error {
            print(error.localizedDescription)
        }
    })
    task.resume()
}

Based on Kyle_the_hacker's -----> answer with my extras.

Ubuntu

In terminal List all locales
locale -a

Install all locales
sudo apt-get install -y locales locales-all

Compile main.cpp
$ g++ main.cpp

Run compiled program
$ ./a.out

Results

Zoë Saldaña played in La maldición del padre Cardona. ëèñ a? óóChloë
Zoë Saldaña played in La maldición del padre Cardona. ëèñ a? óóChloë
ZOË SALDAÑA PLAYED IN LA MALDICIÓN DEL PADRE CARDONA. ËÈÑ ?O ÓÓCHLOË
ZOË SALDAÑA PLAYED IN LA MALDICIÓN DEL PADRE CARDONA. ËÈÑ ?O ÓÓCHLOË
zoë saldaña played in la maldición del padre cardona. ëèñ a? óóchloë
zoë saldaña played in la maldición del padre cardona. ëèñ a? óóchloë

Windows

In cmd run VCVARS developer tools
"C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\VC\Auxiliary\Build\vcvars64.bat"

Compile main.cpp
> cl /EHa main.cpp /D "_DEBUG" /D "_CONSOLE" /D "_UNICODE" /D "UNICODE" /std:c++17 /DYNAMICBASE "kernel32.lib" "user32.lib" "gdi32.lib" "winspool.lib" "comdlg32.lib" "advapi32.lib" "shell32.lib" "ole32.lib" "oleaut32.lib" "uuid.lib" "odbc32.lib" "odbccp32.lib" /MTd

Compilador de optimización de C/C++ de Microsoft (R) versión 19.27.29111 para x64
(C) Microsoft Corporation. Todos los derechos reservados.

main.cpp
Microsoft (R) Incremental Linker Version 14.27.29111.0
Copyright (C) Microsoft Corporation.  All rights reserved.

/out:main.exe
main.obj
kernel32.lib
user32.lib
gdi32.lib
winspool.lib
comdlg32.lib
advapi32.lib
shell32.lib
ole32.lib
oleaut32.lib
uuid.lib
odbc32.lib
odbccp32.lib

Run main.exe
>main.exe

Results

Zoë Saldaña played in La maldición del padre Cardona. ëèñ a? óóChloë
Zoë Saldaña played in La maldición del padre Cardona. ëèñ a? óóChloë
ZOË SALDAÑA PLAYED IN LA MALDICIÓN DEL PADRE CARDONA. ËÈÑ ?O ÓÓCHLOË
ZOË SALDAÑA PLAYED IN LA MALDICIÓN DEL PADRE CARDONA. ËÈÑ ?O ÓÓCHLOË
zoë saldaña played in la maldición del padre cardona. ëèñ a? óóchloë
zoë saldaña played in la maldición del padre cardona. ëèñ a? óóchloë

The code - main.cpp

This code was only tested on Windows x64 and Ubuntu Linux x64.

/*
 * Filename: c:\Users\x\Cpp\main.cpp
 * Path: c:\Users\x\Cpp
 * Filename: /home/x/Cpp/main.cpp
 * Path: /home/x/Cpp
 * Created Date: Saturday, October 17th 2020, 10:43:31 pm
 * Author: Joma
 *
 * No Copyright 2020
 */


#include <iostream>
#include <set>
#include <string>
#include <locale>

// WINDOWS
#if (_WIN32)
#include <Windows.h>
#include <conio.h>
#define WINDOWS_PLATFORM 1
#define DLLCALL STDCALL
#define DLLIMPORT _declspec(dllimport)
#define DLLEXPORT _declspec(dllexport)
#define DLLPRIVATE
#define NOMINMAX

//EMSCRIPTEN
#elif defined(__EMSCRIPTEN__)
#include <emscripten/emscripten.h>
#include <emscripten/bind.h>
#include <unistd.h>
#include <termios.h>
#define EMSCRIPTEN_PLATFORM 1
#define DLLCALL
#define DLLIMPORT
#define DLLEXPORT __attribute__((visibility("default")))
#define DLLPRIVATE __attribute__((visibility("hidden")))

// LINUX - Ubuntu, Fedora, , Centos, Debian, RedHat
#elif (__LINUX__ || __gnu_linux__ || __linux__ || __linux || linux)
#define LINUX_PLATFORM 1
#include <unistd.h>
#include <termios.h>
#define DLLCALL CDECL
#define DLLIMPORT
#define DLLEXPORT __attribute__((visibility("default")))
#define DLLPRIVATE __attribute__((visibility("hidden")))
#define CoTaskMemAlloc(p) malloc(p)
#define CoTaskMemFree(p) free(p)

//ANDROID
#elif (__ANDROID__ || ANDROID)
#define ANDROID_PLATFORM 1
#define DLLCALL
#define DLLIMPORT
#define DLLEXPORT __attribute__((visibility("default")))
#define DLLPRIVATE __attribute__((visibility("hidden")))

//MACOS
#elif defined(__APPLE__)
#include <unistd.h>
#include <termios.h>
#define DLLCALL
#define DLLIMPORT
#define DLLEXPORT __attribute__((visibility("default")))
#define DLLPRIVATE __attribute__((visibility("hidden")))
#include "TargetConditionals.h"
#if TARGET_OS_IPHONE && TARGET_IPHONE_SIMULATOR
#define IOS_SIMULATOR_PLATFORM 1
#elif TARGET_OS_IPHONE
#define IOS_PLATFORM 1
#elif TARGET_OS_MAC
#define MACOS_PLATFORM 1
#else

#endif

#endif



typedef std::string String;
typedef std::wstring WString;

#define EMPTY_STRING u8""s
#define EMPTY_WSTRING L""s

using namespace std::literals::string_literals;

class Strings
{
public:
    static String WideStringToString(const WString& wstr)
    {
        if (wstr.empty())
        {
            return String();
        }
        size_t pos;
        size_t begin = 0;
        String ret;

#if WINDOWS_PLATFORM
        int size;
        pos = wstr.find(static_cast<wchar_t>(0), begin);
        while (pos != WString::npos && begin < wstr.length())
        {
            WString segment = WString(&wstr[begin], pos - begin);
            size = WideCharToMultiByte(CP_UTF8, WC_ERR_INVALID_CHARS, &segment[0], segment.size(), NULL, 0, NULL, NULL);
            String converted = String(size, 0);
            WideCharToMultiByte(CP_UTF8, WC_ERR_INVALID_CHARS, &segment[0], segment.size(), &converted[0], converted.size(), NULL, NULL);
            ret.append(converted);
            ret.append({ 0 });
            begin = pos + 1;
            pos = wstr.find(static_cast<wchar_t>(0), begin);
        }
        if (begin <= wstr.length())
        {
            WString segment = WString(&wstr[begin], wstr.length() - begin);
            size = WideCharToMultiByte(CP_UTF8, WC_ERR_INVALID_CHARS, &segment[0], segment.size(), NULL, 0, NULL, NULL);
            String converted = String(size, 0);
            WideCharToMultiByte(CP_UTF8, WC_ERR_INVALID_CHARS, &segment[0], segment.size(), &converted[0], converted.size(), NULL, NULL);
            ret.append(converted);
        }
#elif LINUX_PLATFORM || MACOS_PLATFORM || EMSCRIPTEN_PLATFORM
        size_t size;
        pos = wstr.find(static_cast<wchar_t>(0), begin);
        while (pos != WString::npos && begin < wstr.length())
        {
            WString segment = WString(&wstr[begin], pos - begin);
            size = wcstombs(nullptr, segment.c_str(), 0);
            String converted = String(size, 0);
            wcstombs(&converted[0], segment.c_str(), converted.size());
            ret.append(converted);
            ret.append({ 0 });
            begin = pos + 1;
            pos = wstr.find(static_cast<wchar_t>(0), begin);
        }
        if (begin <= wstr.length())
        {
            WString segment = WString(&wstr[begin], wstr.length() - begin);
            size = wcstombs(nullptr, segment.c_str(), 0);
            String converted = String(size, 0);
            wcstombs(&converted[0], segment.c_str(), converted.size());
            ret.append(converted);
        }
#else
        static_assert(false, "Unknown Platform");
#endif
        return ret;
    }

    static WString StringToWideString(const String& str)
    {
        if (str.empty())
        {
            return WString();
        }

        size_t pos;
        size_t begin = 0;
        WString ret;
#ifdef WINDOWS_PLATFORM
        int size = 0;
        pos = str.find(static_cast<char>(0), begin);
        while (pos != std::string::npos) {
            std::string segment = std::string(&str[begin], pos - begin);
            std::wstring converted = std::wstring(segment.size() + 1, 0);
            size = MultiByteToWideChar(CP_UTF8, MB_ERR_INVALID_CHARS, &segment[0], segment.size(), &converted[0], converted.length());
            converted.resize(size);
            ret.append(converted);
            ret.append({ 0 });
            begin = pos + 1;
            pos = str.find(static_cast<char>(0), begin);
        }
        if (begin < str.length()) {
            std::string segment = std::string(&str[begin], str.length() - begin);
            std::wstring converted = std::wstring(segment.size() + 1, 0);
            size = MultiByteToWideChar(CP_UTF8, MB_ERR_INVALID_CHARS, segment.c_str(), segment.size(), &converted[0], converted.length());
            converted.resize(size);
            ret.append(converted);
        }

#elif LINUX_PLATFORM || MACOS_PLATFORM || EMSCRIPTEN_PLATFORM
        size_t size;
        pos = str.find(static_cast<char>(0), begin);
        while (pos != String::npos)
        {
            String segment = String(&str[begin], pos - begin);
            WString converted = WString(segment.size(), 0);
            size = mbstowcs(&converted[0], &segment[0], converted.size());
            converted.resize(size);
            ret.append(converted);
            ret.append({ 0 });
            begin = pos + 1;
            pos = str.find(static_cast<char>(0), begin);
        }
        if (begin < str.length())
        {
            String segment = String(&str[begin], str.length() - begin);
            WString converted = WString(segment.size(), 0);
            size = mbstowcs(&converted[0], &segment[0], converted.size());
            converted.resize(size);
            ret.append(converted);
        }
#else
        static_assert(false, "Unknown Platform");
#endif
        return ret;
    }


    static WString ToUpper(const WString& data)
    {
        WString result = data;
        auto& f = std::use_facet<std::ctype<wchar_t>>(std::locale());

        f.toupper(&result[0], &result[0] + result.size());
        return result;
    }

    static String  ToUpper(const String& data)
    {
        return WideStringToString(ToUpper(StringToWideString(data)));
    }

    static WString ToLower(const WString& data)
    {
        WString result = data;
        auto& f = std::use_facet<std::ctype<wchar_t>>(std::locale());
        f.tolower(&result[0], &result[0] + result.size());
        return result;
    }

    static String ToLower(const String& data)
    {
        return WideStringToString(ToLower(StringToWideString(data)));
    }

};

enum class ConsoleTextStyle
{
    DEFAULT = 0,
    BOLD = 1,
    FAINT = 2,
    ITALIC = 3,
    UNDERLINE = 4,
    SLOW_BLINK = 5,
    RAPID_BLINK = 6,
    REVERSE = 7,
};

enum class ConsoleForeground
{
    DEFAULT = 39,
    BLACK = 30,
    DARK_RED = 31,
    DARK_GREEN = 32,
    DARK_YELLOW = 33,
    DARK_BLUE = 34,
    DARK_MAGENTA = 35,
    DARK_CYAN = 36,
    GRAY = 37,
    DARK_GRAY = 90,
    RED = 91,
    GREEN = 92,
    YELLOW = 93,
    BLUE = 94,
    MAGENTA = 95,
    CYAN = 96,
    WHITE = 97
};

enum class ConsoleBackground
{
    DEFAULT = 49,
    BLACK = 40,
    DARK_RED = 41,
    DARK_GREEN = 42,
    DARK_YELLOW = 43,
    DARK_BLUE = 44,
    DARK_MAGENTA = 45,
    DARK_CYAN = 46,
    GRAY = 47,
    DARK_GRAY = 100,
    RED = 101,
    GREEN = 102,
    YELLOW = 103,
    BLUE = 104,
    MAGENTA = 105,
    CYAN = 106,
    WHITE = 107
};

class Console
{
private:
    static void EnableVirtualTermimalProcessing()
    {
#if defined WINDOWS_PLATFORM
        HANDLE hOut = GetStdHandle(STD_OUTPUT_HANDLE);
        DWORD dwMode = 0;
        GetConsoleMode(hOut, &dwMode);
        if (!(dwMode & ENABLE_VIRTUAL_TERMINAL_PROCESSING))
        {
            dwMode |= ENABLE_VIRTUAL_TERMINAL_PROCESSING;
            SetConsoleMode(hOut, dwMode);
        }
#endif
    }

    static void ResetTerminalFormat()
    {
        std::cout << u8"\033[0m";
    }

    static void SetVirtualTerminalFormat(ConsoleForeground foreground, ConsoleBackground background, std::set<ConsoleTextStyle> styles)
    {
        String format = u8"\033[";
        format.append(std::to_string(static_cast<int>(foreground)));
        format.append(u8";");
        format.append(std::to_string(static_cast<int>(background)));
        if (styles.size() > 0)
        {
            for (auto it = styles.begin(); it != styles.end(); ++it)
            {
                format.append(u8";");
                format.append(std::to_string(static_cast<int>(*it)));
            }
        }
        format.append(u8"m");
        std::cout << format;
    }
public:
    static void Clear()
    {

#ifdef WINDOWS_PLATFORM
        std::system(u8"cls");
#elif LINUX_PLATFORM || defined MACOS_PLATFORM
        std::system(u8"clear");
#elif EMSCRIPTEN_PLATFORM
        emscripten::val::global()["console"].call<void>(u8"clear");
#else
        static_assert(false, "Unknown Platform");
#endif
    }

    static void Write(const String& s, ConsoleForeground foreground = ConsoleForeground::DEFAULT, ConsoleBackground background = ConsoleBackground::DEFAULT, std::set<ConsoleTextStyle> styles = {})
    {
#ifndef EMSCRIPTEN_PLATFORM
        EnableVirtualTermimalProcessing();
        SetVirtualTerminalFormat(foreground, background, styles);
#endif
        String str = s;
#ifdef WINDOWS_PLATFORM
        WString unicode = Strings::StringToWideString(str);
        WriteConsole(GetStdHandle(STD_OUTPUT_HANDLE), unicode.c_str(), static_cast<DWORD>(unicode.length()), nullptr, nullptr);
#elif defined LINUX_PLATFORM || defined MACOS_PLATFORM || EMSCRIPTEN_PLATFORM
        std::cout << str;
#else
        static_assert(false, "Unknown Platform");
#endif

#ifndef EMSCRIPTEN_PLATFORM
        ResetTerminalFormat();
#endif
    }

    static void WriteLine(const String& s, ConsoleForeground foreground = ConsoleForeground::DEFAULT, ConsoleBackground background = ConsoleBackground::DEFAULT, std::set<ConsoleTextStyle> styles = {})
    {
        Write(s, foreground, background, styles);
        std::cout << std::endl;
    }

    static void Write(const WString& s, ConsoleForeground foreground = ConsoleForeground::DEFAULT, ConsoleBackground background = ConsoleBackground::DEFAULT, std::set<ConsoleTextStyle> styles = {})
    {
#ifndef EMSCRIPTEN_PLATFORM
        EnableVirtualTermimalProcessing();
        SetVirtualTerminalFormat(foreground, background, styles);
#endif
        WString str = s;

#ifdef WINDOWS_PLATFORM
        WriteConsole(GetStdHandle(STD_OUTPUT_HANDLE), str.c_str(), static_cast<DWORD>(str.length()), nullptr, nullptr);
#elif LINUX_PLATFORM || MACOS_PLATFORM || EMSCRIPTEN_PLATFORM
        std::cout << Strings::WideStringToString(str);
#else
        static_assert(false, "Unknown Platform");
#endif

#ifndef EMSCRIPTEN_PLATFORM
        ResetTerminalFormat();
#endif
    }

    static void WriteLine(const WString& s, ConsoleForeground foreground = ConsoleForeground::DEFAULT, ConsoleBackground background = ConsoleBackground::DEFAULT, std::set<ConsoleTextStyle> styles = {})
    {
        Write(s, foreground, background, styles);
        std::cout << std::endl;
    }

    static void WriteLine()
    {
        std::cout << std::endl;
    }

    static void Pause()
    {
        char c;
        do
        {
            c = getchar();
            std::cout << "Press Key " << std::endl;
        } while (c != 64);
        std::cout << "KeyPressed" << std::endl;
    }

    static int PauseAny(bool printWhenPressed = false, ConsoleForeground foreground = ConsoleForeground::DEFAULT, ConsoleBackground background = ConsoleBackground::DEFAULT, std::set<ConsoleTextStyle> styles = {})
    {
        int ch;
#ifdef WINDOWS_PLATFORM
        ch = _getch();
#elif LINUX_PLATFORM || MACOS_PLATFORM || EMSCRIPTEN_PLATFORM
        struct termios oldt, newt;
        tcgetattr(STDIN_FILENO, &oldt);
        newt = oldt;
        newt.c_lflag &= ~(ICANON | ECHO);
        tcsetattr(STDIN_FILENO, TCSANOW, &newt);
        ch = getchar();
        tcsetattr(STDIN_FILENO, TCSANOW, &oldt);
#else
        static_assert(false, "Unknown Platform");
#endif
        if (printWhenPressed)
        {
            Console::Write(String(1, ch), foreground, background, styles);
        }
        return ch;
    }
};



int main()
{
    std::locale::global(std::locale(u8"en_US.UTF-8"));
    String dataStr = u8"Zoë Saldaña played in La maldición del padre Cardona. ëèñ a? óóChloë";
    WString dataWStr = L"Zoë Saldaña played in La maldición del padre Cardona. ëèñ a? óóChloë";
    std::string locale = u8"";
    //std::string locale = u8"de_DE.UTF-8";
    //std::string locale = u8"en_US.UTF-8";
    Console::WriteLine(dataStr);
    Console::WriteLine(dataWStr);
    dataStr = Strings::ToUpper(dataStr);
    dataWStr = Strings::ToUpper(dataWStr);
    Console::WriteLine(dataStr);
    Console::WriteLine(dataWStr);
    dataStr = Strings::ToLower(dataStr);
    dataWStr = Strings::ToLower(dataWStr);
    Console::WriteLine(dataStr);
    Console::WriteLine(dataWStr);
    
    
    Console::WriteLine(u8"Press any key to exit"s, ConsoleForeground::DARK_GRAY);
    Console::PauseAny();

    return 0;
}

This is my solution for my scenario:

<div class="btn-group btn-group-justified">
    <a class="btn btn-default" ng-class="{'btn-success': hover.left, 'btn-danger': hover.right}" ng-click="setMatch(-1)" role="button" ng-mouseenter="hover.left = true;" ng-mouseleave="hover.left = false;">
        <i class="fa fa-thumbs-o-up fa-5x pull-left" ng-class="{'fa-rotate-90': !hover.left && !hover.right, 'fa-flip-vertical': hover.right}"></i>
        {{ song.name }}
    </a>
    <a class="btn btn-default" ng-class="{'btn-success': hover.right, 'btn-danger': hover.left}" ng-click="setMatch(1)" role="button" ng-mouseenter="hover.right = true;" ng-mouseleave="hover.right = false;">
        <i class="fa fa-thumbs-o-up fa-5x pull-right" ng-class="{'fa-rotate-270': !hover.left && !hover.right, 'fa-flip-vertical': hover.left}"></i>
        {{ match.name }}
    </a>
</div>

default state:

on hover:

String one = object.getdata();
Log.d(one,"");

I converted sav to csv online: http://pspp.benpfaff.org/

If you are using C#, you do not need to escape it.

Angular filters can only be applied to arrays and not objects, from angular's API -

"Selects a subset of items from array and returns it as a new array."

You have two options here:
1) move $scope.items to an array or -
2) pre-filter the ng-repeat items, like this:

<div ng-repeat="(k,v) in filterSecId(items)">
    {{k}} {{v.pos}}
</div>

And on the Controller:

$scope.filterSecId = function(items) {
    var result = {};
    angular.forEach(items, function(value, key) {
        if (!value.hasOwnProperty('secId')) {
            result[key] = value;
        }
    });
    return result;
}

jsfiddle: http://jsfiddle.net/bmleite/WA2BE/

I am just going to post the answer for python so people will have a reference.

from win32com.client import Dispatch
from win32com.client import constants
import win32com.client

xlApp = Dispatch("Excel.Application")
xlWb = xlApp.Workbooks.Open(filename_xls)
ws = xlWb.Worksheets(1)
xlApp.Visible=False
xlWbTemplate = xlApp.Workbooks.Open('otherfile.xls')
ws_sub = xlWbTemplate.Worksheets(1)
ws_sub.Activate()
xlWbTemplate.Worksheets(2).Copy(None,xlWb.Worksheets(1))
ws_sub = xlWbTemplate.Worksheets(2)
ws_sub.Activate()

xlWbTemplate.Close(SaveChanges=0)
xlWb.Worksheets(1).Activate()
xlWb.Close(SaveChanges=1)
xlApp.Quit()

Beware the leading 00 that can appear in the modulus when using:

openssl rsa -pubin -inform PEM -text -noout < public.key

The example modulus contains 257 bytes rather than 256 bytes because of that 00, which is included because the 9 in 98 looks like a negative signed number.

jspdf and Angular 8

I generate a pdf and want to upload the pdf with POST request, this is how I do (For clarity, I delete some of the code and service layer)

import * as jsPDF from 'jspdf';
import { HttpClient } from '@angular/common/http';

constructor(private http: HttpClient)

upload() {
    const pdf = new jsPDF()
    const blob = pdf.output('blob')
    const formData = new FormData()
    formData.append('file', blob)
    this.http.post('http://your-hostname/api/upload', formData).subscribe()
}

Yo could also set labels = FALSE inside axis(...) and print the labels in a separate command with Text. With this option you can rotate the text the text in case you need it

lablist<-as.vector(c(1:10))
axis(1, at=seq(1, 10, by=1), labels = FALSE)
text(seq(1, 10, by=1), par("usr")[3] - 0.2, labels = lablist, srt = 45, pos = 1, xpd = TRUE)

Detailed explanation here

Sorry you're not using PostgreSQL...

SELECT DISTINCT ON contract, activity * FROM thetable ORDER BY contract, activity

http://www.postgresql.org/docs/8.3/static/sql-select.html#SQL-DISTINCT

Oh wait. You only want values with exactly one...

SELECT contract, activity, count() FROM thetable GROUP BY contract, activity HAVING count() = 1

Use the password input type.

<input type="password" name="password" />

Here is a simple demo http://jsfiddle.net/cPaEN/

They say it right there in the documentation for the FPDF constructor:

FPDF([string orientation [, string unit [, mixed size]]])

This is the class constructor. It allows to set up the page size, the orientation and the unit of measure used in all methods (except for font sizes). Parameters ...

size

The size used for pages. It can be either one of the following values (case insensitive):

A3 A4 A5 Letter Legal

or an array containing the width and the height (expressed in the unit given by unit).

They even give an example with custom size:

Example with a custom 100x150 mm page size:

$pdf = new FPDF('P','mm',array(100,150));

Yes, NSDictionary supports fast enumeration. With Objective-C 2.0, you can do this:

// To print out all key-value pairs in the NSDictionary myDict
for(id key in myDict)
    NSLog(@"key=%@ value=%@", key, [myDict objectForKey:key]);

The alternate method (which you have to use if you're targeting Mac OS X pre-10.5, but you can still use on 10.5 and iPhone) is to use an NSEnumerator:

NSEnumerator *enumerator = [myDict keyEnumerator];
id key;
// extra parens to suppress warning about using = instead of ==
while((key = [enumerator nextObject]))
    NSLog(@"key=%@ value=%@", key, [myDict objectForKey:key]);

In order to avoid the black background when starting an activity already in the stack, I added overridePendingTransition(0,0) in onStart():

@Override
protected void onStart() {
    overridePendingTransition(0,0);
    super.onStart();

}

Do you mean like this

int index = 2;
string s = "hello";
Console.WriteLine(s[index]);

string also implements IEnumberable<char> so you can also enumerate it like this

foreach (char c in s)
    Console.WriteLine(c);

This won't work for InnoDB. Use this workaround only if you are trying to copy MyISAM databases.

If locking the tables during backup, and, possibly, pausing MySQL during the database import is acceptable, mysqlhotcopy may work faster.

E.g.

Backup:

# mysqlhotcopy -u root -p password db_name /path/to/backup/directory

Restore:

cp /path/to/backup/directory/* /var/lib/mysql/db_name

mysqlhotcopy can also transfer files over SSH (scp), and, possibly, straight into the duplicate database directory.

E.g.

# mysqlhotcopy -u root -p password db_name /var/lib/mysql/duplicate_db_name

bool data(sampleData *data)
{
}

You need to tell the method which type of struct you are using. In this case, sampleData.

Note: In this case, you will need to define the struct prior to the method for it to be recognized.

Example:

struct sampleData
{
   int N;
   int M;
   // ...
};

bool data(struct *sampleData)
{

}

int main(int argc, char *argv[]) {

      sampleData sd;
      data(&sd);

}

Note 2: I'm a C guy. There may be a more c++ish way to do this.

I ran into the same issue today, try running ur container with this command.

docker run --name mariadbtest -p 3306:3306 -e MYSQL_ROOT_PASSWORD=mypass -d mariadb/server:10.3

Here is the MooTools date picker

http://www.monkeyphysics.com/mootools/script/2/datepicker Example http://www.monkeyphysics.com/mootools/script/2/datepicker#examples

If you want to filter y active accounts add this to Harvey's code:

 UserPrincipal userPrin = new UserPrincipal(context);
 userPrin.Enabled = true;

after the first using. Then add

  searcher.QueryFilter = userPrin;

before the find all. And that should get you the active ones.

Use RxJS in a Service

What about in a situation where you have a Service that's holding state for example. How could I push changes to that Service, and other random components on the page be aware of such a change? Been struggling with tackling this problem lately

Build a service with RxJS Extensions for Angular.

<script src="//unpkg.com/angular/angular.js"></script>
<script src="//unpkg.com/rx/dist/rx.all.js"></script>
<script src="//unpkg.com/rx-angular/dist/rx.angular.js"></script>

var app = angular.module('myApp', ['rx']);

app.factory("DataService", function(rx) {
  var subject = new rx.Subject(); 
  var data = "Initial";

  return {
      set: function set(d){
        data = d;
        subject.onNext(d);
      },
      get: function get() {
        return data;
      },
      subscribe: function (o) {
         return subject.subscribe(o);
      }
  };
});

Then simply subscribe to the changes.

app.controller('displayCtrl', function(DataService) {
  var $ctrl = this;

  $ctrl.data = DataService.get();
  var subscription = DataService.subscribe(function onNext(d) {
      $ctrl.data = d;
  });

  this.$onDestroy = function() {
      subscription.dispose();
  };
});

Clients can subscribe to changes with DataService.subscribe and producers can push changes with DataService.set.

The DEMO on PLNKR.

If you're using zsh, you can use multiple redirections, so you don't even need tee:

./cmd 1>&1 2>&2 1>out_file 2>err_file

Here you're simply redirecting each stream to itself and the target file.

Full example

% (echo "out"; echo "err">/dev/stderr) 1>&1 2>&2 1>/tmp/out_file 2>/tmp/err_file
out
err
% cat /tmp/out_file
out
% cat /tmp/err_file
err

Note that this requires the MULTIOS option to be set (which is the default).

MULTIOS

Perform implicit tees or cats when multiple redirections are attempted (see Redirection).

You can print to file and at the same time see progress having (or not) screen, while running a R script.

When not using screen, use R CMD BATCH yourscript.R & and step 4.

1. When using screen, in a terminal, start screen

    screen
   

2. run your R script

    R CMD BATCH yourscript.R
   

3. Go to another screen pressing CtrlA, then c

4. look at your output with (real-time):

    tail -f yourscript.Rout
   

5. Switch among screens with CtrlA then n

If the other answers aren't working for you, there's also a homepage field in package.json. After running npm run build you should get a message like the following:

The project was built assuming it is hosted at the server root.
To override this, specify the homepage in your package.json.
For example, add this to build it for GitHub Pages:

  "homepage" : "http://myname.github.io/myapp",

You would just add it as one of the root fields in package.json, e.g.

{
  // ...
  "scripts": {
    // ...
  },
  "homepage": "https://example.com"
}

When it's successfully set, either via homepage or PUBLIC_URL, you should instead get a message like this:

The project was built assuming it is hosted at https://example.com.
You can control this with the homepage field in your package.json.

Try using mongoose function for pagination. Limit is the number of records per page and number of the page.

var limit = parseInt(body.limit);
var skip = (parseInt(body.page)-1) * parseInt(limit);

 db.Rankings.find({})
            .sort('-id')
            .limit(limit)
            .skip(skip)
            .exec(function(err,wins){
 });

If you're going to reuse the value like an id or if you want to just keep it you can add a "new{id = 'desiredID/value'}) as its parameters so you can access the value thru jquery/javascript

@Html.HiddenFor(model => model.Car_id)

This error happens when you have a ViewBag Non-Existent in your razor code calling a method.

Controller

public ActionResult Accept(int id)
{
    return View();
}

razor:

<div class="form-group">
      @Html.LabelFor(model => model.ToId, "To", htmlAttributes: new { @class = "control-label col-md-2" })
     <div class="col-md-10">
           @Html.Flag(Model.from)
     </div>
</div>
<div class="form-group">
     <div class="col-md-10">
          <input value="@ViewBag.MaximounAmount.ToString()" />@* HERE is the error *@ 
     </div>
</div>

For some reason, the .net aren't able to show the error in the correct line.

Normally this causes a lot of wasted time.

#!/bin/bash
ping_count="4"
avg_max_limit="1500"
router="sagemcom-fast-2804-v2"
adress="192.168.1.1"
user="admin"
pass="admin"

VAR=$(
expect -c " 
        set timeout 3
        spawn telnet "$adress"
        expect \"Login:\" 
        send \"$user\n\"
        expect \"Password:\"
        send \"$pass\n\"
        expect \"commands.\"
        send \"ping ya.ru -c $ping_count\n\"
        set timeout 9
        expect \"transmitted\"
        send \"exit\"
        ")

count_ping=$(echo "$VAR" | grep packets | cut -c 1)
avg_ms=$(echo "$VAR" | grep round-trip | cut -d '/' -f 4 | cut -d '.' -f 1)

echo "1_____ping___$count_ping|||____$avg_ms"
echo "$VAR"

{{#each array}}
  {{@index}}
{{/each}}

Gone through the already posted answers. Just thought it would be better if I add an answer with actual example.

Let' say you have 3 Django models which are related.

class M1(models.Model):
    name = models.CharField(max_length=10)

class M2(models.Model):
    name = models.CharField(max_length=10)
    select_relation = models.ForeignKey(M1, on_delete=models.CASCADE)
    prefetch_relation = models.ManyToManyField(to='M3')

class M3(models.Model):
    name = models.CharField(max_length=10)

Here you can query M2 model and its relative M1 objects using select_relation field and M3 objects using prefetch_relation field.

However as we've mentioned M1's relation from M2 is a ForeignKey, it just returns only 1 record for any M2 object. Same thing applies for OneToOneField as well.

But M3's relation from M2 is a ManyToManyField which might return any number of M1 objects.

Consider a case where you have 2 M2 objects m21, m22 who have same 5 associated M3 objects with IDs 1,2,3,4,5. When you fetch associated M3 objects for each of those M2 objects, if you use select related, this is how it's going to work.

Steps:

1. Find m21 object.
2. Query all the M3 objects related to m21 object whose IDs are 1,2,3,4,5.
3. Repeat same thing for m22 object and all other M2 objects.

As we have same 1,2,3,4,5 IDs for both m21, m22 objects, if we use select_related option, it's going to query the DB twice for the same IDs which were already fetched.

Instead if you use prefetch_related, when you try to get M2 objects, it will make a note of all the IDs that your objects returned (Note: only the IDs) while querying M2 table and as last step, Django is going to make a query to M3 table with the set of all IDs that your M2 objects have returned. and join them to M2 objects using Python instead of database.

This way you're querying all the M3 objects only once which improves performance.

To anyone still struggling, be sure to check and see if you've set a line-height value on the font in question: it could be overriding the word wrap.

The foreign keys in your schema (on Account_Name and Account_Type) do not require any special treatment or syntax. Just declare two separate foreign keys on the Customer table. They certainly don't constitute a composite key in any meaningful sense of the word.

There are numerous other problems with this schema, but I'll just point out that it isn't generally a good idea to build a primary key out of multiple unique columns, or columns in which one is functionally dependent on another. It appears that at least one of these cases applies to the ID and Name columns in the Customer table. This allows you to create two rows with the same ID (different name), which I'm guessing you don't want to allow.

Off the top of my head, you can eliminate the lambda:

reduce(list.__add__, map(list, [mi.image_set.all() for mi in list_of_menuitems]))

Or even eliminate the map, since you've already got a list-comp:

reduce(list.__add__, [list(mi.image_set.all()) for mi in list_of_menuitems])

You can also just express this as a sum of lists:

sum([list(mi.image_set.all()) for mi in list_of_menuitems], [])

Sure it's possible... use Export Wizard in source option use SQL SERVER NATIVE CLIENT 11, later your source server ex.192.168.100.65\SQLEXPRESS next step select your new destination server ex.192.168.100.65\SQL2014

Just be sure to be using correct instance and connect each other

Just pay attention in Stored procs must be recompiled

Here's the yaml dictConfig way recommended for 3.2 & later.

In log cfg.yml:

version: 1
disable_existing_loggers: true

formatters:
    default:
        format: "[%(process)d] %(name)s(%(funcName)s:%(lineno)s) - %(levelname)s: %(message)s"

handlers:
    syslog:
        class: logging.handlers.SysLogHandler
        level: DEBUG
        formatter: default
        address: /dev/log
        facility: local0

    rotating_file:
        class: logging.handlers.RotatingFileHandler
        level: DEBUG
        formatter: default
        filename: rotating.log
        maxBytes: 10485760 # 10MB
        backupCount: 20
        encoding: utf8

root:
    level: DEBUG
    handlers: [syslog, rotating_file]
    propogate: yes

loggers:
    main:
        level: DEBUG
        handlers: [syslog, rotating_file]
        propogate: yes

Load the config using:

log_config = yaml.safe_load(open('cfg.yml'))
logging.config.dictConfig(log_config)

Configured both syslog & a direct file. Note that the /dev/log is OS specific.

Add this to your CSS:

ul { list-style-position: inside; }

This will place the li elements in the same indent as other paragraphs and text.

Ref: http://www.w3schools.com/cssref/pr_list-style-position.asp

Maybe It can be perfect example for Android, For example:

void setWaitScreen(boolean set) {
    findViewById(R.id.screen_main).setVisibility(
            set ? View.GONE : View.VISIBLE);
    findViewById(R.id.screen_wait).setVisibility(
            set ? View.VISIBLE : View.GONE);
}

I'm using simple alias to create pull request,

alias pr='open -n -a "Google Chrome" --args "https://github.com/user/repo/compare/pre-master...nawarkhede:$(git_current_branch)\?expand\=1"'

You can call another constructor via the this(...) keyword (when you need to call a constructor from the same class) or the super(...) keyword (when you need to call a constructor from a superclass).

However, such a call must be the first statement of your constructor. To overcome this limitation, use this answer.

To delete local branches that have been merged to master branch I'm using the following alias (git config -e --global):

cleanup = "!git branch --merged master | grep -v '^*\\|master' | xargs -n 1 git branch -D"

I'm using git branch -D to avoid error: The branch 'some-branch' is not fully merged. messages while my current checkout is different from master branch.

Hi use this class this will compare both lists and shows exactly the mismatch b/w both lists.

import java.util.ArrayList;
import java.util.List;


public class ListCompare {

    /**
     * @param args
     */
    public static void main(String[] args) {
        List<String> dbVinList;
        dbVinList = new ArrayList<String>();
        List<String> ediVinList;
        ediVinList = new ArrayList<String>();           

        dbVinList.add("A");
        dbVinList.add("B");
        dbVinList.add("C");
        dbVinList.add("D");

        ediVinList.add("A");
        ediVinList.add("C");
        ediVinList.add("E");
        ediVinList.add("F");
        /*ediVinList.add("G");
        ediVinList.add("H");
        ediVinList.add("I");
        ediVinList.add("J");*/  

        List<String> dbVinListClone = dbVinList;
        List<String> ediVinListClone = ediVinList;

        boolean flag;
        String mismatchVins = null;
        if(dbVinListClone.containsAll(ediVinListClone)){
            flag = dbVinListClone.removeAll(ediVinListClone);   
            if(flag){
                mismatchVins = getMismatchVins(dbVinListClone);
            }
        }else{
            flag = ediVinListClone.removeAll(dbVinListClone);
            if(flag){
                mismatchVins = getMismatchVins(ediVinListClone);
            }
        }
        if(mismatchVins != null){
            System.out.println("mismatch vins : "+mismatchVins);
        }       

    }

    private static String getMismatchVins(List<String> mismatchList){
        StringBuilder mismatchVins = new StringBuilder();
        int i = 0;
        for(String mismatch : mismatchList){
            i++;
            if(i < mismatchList.size() && i!=5){
                mismatchVins.append(mismatch).append(",");  
            }else{
                mismatchVins.append(mismatch);
            }
            if(i==5){               
                break;
            }
        }
        String mismatch1;
        if(mismatchVins.length() > 100){
            mismatch1 = mismatchVins.substring(0, 99);
        }else{
            mismatch1 = mismatchVins.toString();
        }       
        return mismatch1;
    }

}

Use position property

style="position: absolute;right:0;top:0"

Try this:

- (void)tableView:(UITableView *)tableView1 willDisplayCell:(UITableViewCell *)cell forRowAtIndexPath:(NSIndexPath *)indexPath
{
    [cell setBackgroundColor:[UIColor clearColor]];
    tableView1.backgroundColor = [UIColor colorWithPatternImage: [UIImage imageNamed: @"Cream.jpg"]];
}

You need to use either the globals loader or expose loader to ensure that webpack includes the jQuery lib in your source code output and so that it doesn't throw errors when your use $ in your components.

// example with expose loader:
npm i --save-dev expose-loader

// somewhere, import (require) this jquery, but pipe it through the expose loader
require('expose?$!expose?jQuery!jquery')

If you prefer, you can import (require) it directly within your webpack config as a point of entry, so I understand, but I don't have an example of this to hand

Alternatively, you can use the globals loader like this: https://www.npmjs.com/package/globals-loader

You can't: It's a security feature in all modern browsers.

For IE8, it's off by default, but can be reactivated using a security setting:

When a file is selected by using the input type=file object, the value of the value property depends on the value of the "Include local directory path when uploading files to a server" security setting for the security zone used to display the Web page containing the input object.

The fully qualified filename of the selected file is returned only when this setting is enabled. When the setting is disabled, Internet Explorer 8 replaces the local drive and directory path with the string C:\fakepath\ in order to prevent inappropriate information disclosure.

In all other current mainstream browsers I know of, it is also turned off. The file name is the best you can get.

More detailed info and good links in this question. It refers to getting the value server-side, but the issue is the same in JavaScript before the form's submission.

It works perfectly in my case.

document.getElementById("form1").submit();

Also, you can use it in a function as below:

function formSubmit()
{
    document.getElementById("form1").submit();
}

Make a script like this:

#!/bin/bash

echo $((0x$1)).$((0x$2)).$((0x$3)).$((0x$4))

Example:

sh converthextoip.sh c0 a8 00 0b

Result:

192.168.0.11

Whenever you want to use variable variables, it's probably better to use a dictionary. So instead of writing

$foo = "bar"
$$foo = "baz"

you write

mydict = {}
foo = "bar"
mydict[foo] = "baz"

This way you won't accidentally overwrite previously existing variables (which is the security aspect) and you can have different "namespaces".

The error shows that the machine does not have enough memory to read the entire CSV into a DataFrame at one time. Assuming you do not need the entire dataset in memory all at one time, one way to avoid the problem would be to process the CSV in chunks (by specifying the chunksize parameter):

chunksize = 10 ** 6
for chunk in pd.read_csv(filename, chunksize=chunksize):
    process(chunk)

The chunksize parameter specifies the number of rows per chunk. (The last chunk may contain fewer than chunksize rows, of course.)

pandas >= 1.2

read_csv with chunksize returns a context manager, to be used like so:

chunksize = 10 ** 6
with pd.read_csv(filename, chunksize=chunksize) as reader:
    for chunk in reader:
        process(chunk)

See GH38225

Browsing this comment section I came accross two different patterns answering the question. Sadly for SQL 2012, the second pattern doesn't work, so here's my "work around"

Order By on a Common Column

This is the easiest case you can encounter. Like many user pointed out, all you really need to do is add an Order By at the end of the query

SELECT a FROM table1
UNION
SELECT a FROM table2
ORDER BY field1

or

SELECT a FROM table1 ORDER BY field1
UNION
SELECT a FROM table2 ORDER BY field1

Order By on Different Columns

Here's where it actually gets tricky. Using SQL 2012, I tried the top post and it doesn't work.

SELECT * FROM 
(
  SELECT table1.field1 FROM table1 ORDER BY table1.field1
) DUMMY_ALIAS1

UNION ALL

SELECT * FROM
( 
  SELECT table2.field1 FROM table2 ORDER BY table2.field1
) DUMMY_ALIAS2

Following the recommandation in the comment I tried this

SELECT * FROM 
(
  SELECT TOP 100 PERCENT table1.field1 FROM table1 ORDER BY table1.field1
) DUMMY_ALIAS1

UNION ALL

SELECT * FROM
( 
  SELECT TOP 100 PERCENT table2.field1 FROM table2 ORDER BY table2.field1
) DUMMY_ALIAS2

This code did compile but the DUMMY_ALIAS1 and DUMMY_ALIAS2 override the Order By established in the Select statement which makes this unusable.

The only solution that I could think of, that worked for me was not using a union and instead making the queries run individually and then dealing with them. So basically, not using a Union when you want to Order By

The question raised in 2014 and it's 2019 so I guess it's good to look for better option.

You can simply use fetch api in Javascript which provide you more flexibility.

for example, see this code

fetch('./api/some.json')
    .then((response) => {
        response.json().then((data) => { 
            ... 
        });
    })
    .catch((err) => { ... });

To enable this app-wide, I created a category on UIWindow:

@implementation UIWindow (Utils)

- (BOOL)canBecomeFirstResponder
{
    return YES;
}

- (void)motionBegan:(UIEventSubtype)motion withEvent:(UIEvent *)event
{
    if (motion == UIEventSubtypeMotionShake) {
        // Do whatever you want here...
    }
}

@end

Use options(scipen=5) or some other high enough number. The scipen option determines how likely R is to switch to scientific notation, the higher the value the less likely it is to switch. Set the option before making your plot, if it still has scientific notation, set it to a higher number.

…another lambda
copying a new string from the original, but leaving out the character that is to delete

String text = "removing a special character from a string";

int delete = 'e';
int[] arr = text.codePoints().filter( c -> c != delete ).toArray();

String rslt = new String( arr, 0, arr.length );

gives: rmoving a spcial charactr from a string

You can use the parseInt() function to convert the string to a number, e.g:

parseInt($('#elem').css('top'));

Update: (as suggested by Ben): You should give the radix too:

parseInt($('#elem').css('top'), 10);

Forces it to be parsed as a decimal number, otherwise strings beginning with '0' might be parsed as an octal number (might depend on the browser used).

As long as ManagementObjectCollection implements IEnumerable<ManagementObject> you can do:

List<ManagementObject> managementList = new List<ManagementObjec>(managementObjects);

If it doesn't, then you are stuck doing it the way that you are doing it.

use this query in your local DB.

1. select * from schema_version delete from schema_version where checksum Column = -1729781252;

   Note: -1729781252 is the "Resolved locally" value.

2. Build and start the server.

JPG doesn't support transparency

Can this be done with bootstrap 3's carousel? I'm hoping I won't have to go hunting for yet another jQuery plugin

As of 2013-12-08 the answer is no. The effect you are looking for is not possible using Bootstrap 3's generic carousel plugin. However, here's a simple jQuery plugin that seems to do exactly what you want http://sorgalla.com/jcarousel/

You can just use the pipe on its own:

"string1|string2"

for example:

String s = "string1, string2, string3";
System.out.println(s.replaceAll("string1|string2", "blah"));

Output:

blah, blah, string3

The main reason to use parentheses is to limit the scope of the alternatives:

String s = "string1, string2, string3";
System.out.println(s.replaceAll("string(1|2)", "blah"));

has the same output. but if you just do this:

String s = "string1, string2, string3";
System.out.println(s.replaceAll("string1|2", "blah"));

you get:

blah, stringblah, string3

because you've said "string1" or "2".

If you don't want to capture that part of the expression use ?::

String s = "string1, string2, string3";
System.out.println(s.replaceAll("string(?:1|2)", "blah"));

2D scatter plot

Using the scatter method of the matplotlib.pyplot module should work (at least with matplotlib 1.2.1 with Python 2.7.5), as in the example code below. Also, if you are using scatter plots, use scatterpoints=1 rather than numpoints=1 in the legend call to have only one point for each legend entry.

In the code below I've used random values rather than plotting the same range over and over, making all the plots visible (i.e. not overlapping each other).

import matplotlib.pyplot as plt
from numpy.random import random

colors = ['b', 'c', 'y', 'm', 'r']

lo = plt.scatter(random(10), random(10), marker='x', color=colors[0])
ll = plt.scatter(random(10), random(10), marker='o', color=colors[0])
l  = plt.scatter(random(10), random(10), marker='o', color=colors[1])
a  = plt.scatter(random(10), random(10), marker='o', color=colors[2])
h  = plt.scatter(random(10), random(10), marker='o', color=colors[3])
hh = plt.scatter(random(10), random(10), marker='o', color=colors[4])
ho = plt.scatter(random(10), random(10), marker='x', color=colors[4])

plt.legend((lo, ll, l, a, h, hh, ho),
           ('Low Outlier', 'LoLo', 'Lo', 'Average', 'Hi', 'HiHi', 'High Outlier'),
           scatterpoints=1,
           loc='lower left',
           ncol=3,
           fontsize=8)

plt.show()

3D scatter plot

To plot a scatter in 3D, use the plot method, as the legend does not support Patch3DCollection as is returned by the scatter method of an Axes3D instance. To specify the markerstyle you can include this as a positional argument in the method call, as seen in the example below. Optionally one can include argument to both the linestyle and marker parameters.

import matplotlib.pyplot as plt
from numpy.random import random
from mpl_toolkits.mplot3d import Axes3D

colors=['b', 'c', 'y', 'm', 'r']

ax = plt.subplot(111, projection='3d')

ax.plot(random(10), random(10), random(10), 'x', color=colors[0], label='Low Outlier')
ax.plot(random(10), random(10), random(10), 'o', color=colors[0], label='LoLo')
ax.plot(random(10), random(10), random(10), 'o', color=colors[1], label='Lo')
ax.plot(random(10), random(10), random(10), 'o', color=colors[2], label='Average')
ax.plot(random(10), random(10), random(10), 'o', color=colors[3], label='Hi')
ax.plot(random(10), random(10), random(10), 'o', color=colors[4], label='HiHi')
ax.plot(random(10), random(10), random(10), 'x', color=colors[4], label='High Outlier')

plt.legend(loc='upper left', numpoints=1, ncol=3, fontsize=8, bbox_to_anchor=(0, 0))

plt.show()

Here's a simple one liner

$ip = $_SERVER['HTTP_X_FORWARDED_FOR']?: $_SERVER['HTTP_CLIENT_IP']?: $_SERVER['REMOTE_ADDR'];

EDIT:

Above code may return reserved addresses (like 10.0.0.1), a list of addresses of all proxy servers on the way, etc. To handle these cases use the following code:

function valid_ip($ip) {
    // for list of reserved IP addresses, see https://en.wikipedia.org/wiki/Reserved_IP_addresses
    return $ip && substr($ip, 0, 4) != '127.' && substr($ip, 0, 4) != '127.' && substr($ip, 0, 3) != '10.' && substr($ip, 0, 2) != '0.' ? $ip : false;
}

function get_client_ip() {
    // using explode to get only client ip from list of forwarders. see https://en.wikipedia.org/wiki/X-Forwarded-For
    return
    @$_SERVER['HTTP_X_FORWARDED_FOR'] ? explode(',', $_SERVER['HTTP_X_FORWARDED_FOR'], 2)[0] :
    @$_SERVER['HTTP_CLIENT_IP'] ? explode(',', $_SERVER['HTTP_CLIENT_IP'], 2)[0] :
    valid_ip(@$_SERVER['REMOTE_ADDR']) ?:
    'UNKNOWN';
}

echo get_client_ip();

It is even easier in Swift:

let string : String = "Hello  "
let characters = Array(string)
println(characters)
// [H, e, l, l, o,  , , ,  , ]

This uses the facts that

• an Array can be created from a SequenceType, and
• String conforms to the SequenceType protocol, and its sequence generator enumerates the characters.

And since Swift strings have full support for Unicode, this works even with characters outside of the "Basic Multilingual Plane" (such as ) and with extended grapheme clusters (such as , which is actually composed of two Unicode scalars).

Update: As of Swift 2, String does no longer conform to SequenceType, but the characters property provides a sequence of the Unicode characters:

let string = "Hello  "
let characters = Array(string.characters)
print(characters)

This works in Swift 3 as well.

Update: As of Swift 4, String is (again) a collection of its Characters:

let string = "Hello  "
let characters = Array(string)
print(characters)
// ["H", "e", "l", "l", "o", " ", "", "", " ", ""]

here's a short paragraph from this article How to Make Frames (Main Windows) - The Java Tutorials - Oracle that explains what setBounds method does in addition to some other similar methods:

The pack method sizes the frame so that all its contents are at or above their preferred sizes. An alternative to pack is to establish a frame size explicitly by calling setSize or setBounds (which also sets the frame location). In general, using pack is preferable to calling setSize, since pack leaves the frame layout manager in charge of the frame size, and layout managers are good at adjusting to platform dependencies and other factors that affect component size.

the parameters of setBounds are (int x, int y, int width, int height) x and y are define the position/location and width and height define the size/dimension of the frame.

By specifying the column as VARCHAR(500) you've set an explicit 500 character limit. You might not have done this yourself explicitly, but Django has done it for you somewhere. Telling you where is hard when you haven't shown your model, the full error text, or the query that produced the error.

If you don't want one, use an unqualified VARCHAR, or use the TEXT type.

varchar and text are limited in length only by the system limits on column size - about 1GB - and by your memory. However, adding a length-qualifier to varchar sets a smaller limit manually. All of the following are largely equivalent:

column_name VARCHAR(500)

column_name VARCHAR CHECK (length(column_name) <= 500) 

column_name TEXT CHECK (length(column_name) <= 500) 

The only differences are in how database metadata is reported and which SQLSTATE is raised when the constraint is violated.

The length constraint is not generally obeyed in prepared statement parameters, function calls, etc, as shown:

regress=> \x
Expanded display is on.
regress=> PREPARE t2(varchar(500)) AS SELECT $1;
PREPARE
regress=> EXECUTE t2( repeat('x',601) );
-[ RECORD 1 ]-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
?column? | xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

and in explicit casts it result in truncation:

regress=> SELECT repeat('x',501)::varchar(1);
-[ RECORD 1 ]
repeat | x

so I think you are using a VARCHAR(500) column, and you're looking at the wrong table or wrong instance of the database.

My Problem:

• I started a container with docker run <IMAGE_NAME>
• And then added some files to this container
• Then I closed the container and tried to start it again withe same command as above.
• But when I checked the new files, they were missing
• when I run docker ps -a I could see two containers.
• That means every time I was running docker run <IMAGE_NAME> command, new image was getting created

Solution: To work on the same container you created in the first place run follow these steps

• docker ps to get container of your container
• docker container start <CONTAINER_ID> to start existing container
• Then you can continue from where you left. e.g. docker exec -it <CONTAINER_ID> /bin/bash
• You can then decide to create a new image out of it

Compare Side-By-Side looks like the most convenient to me though it's not the most popular:

UPD: I need to add that this plugin can freeze ST while comparing big files. It is certainly not the best decision if you are going to compare large texts.

The exception message says you're trying to connect to the same host (127.0.0.1), while you're stating that your server is running on a different host. Besides the obvious bugs like having "localhost" in the url, or maybe some you might want to check your DNS settings.

This is always fascinating. I am not a cloud developer, but based on my research there is nothing significantly different than what many of us have been doing off and on for decades. The server is platform specific. If you want to write platform agnostic code for your server that is fine, but unnecessary based on whoever your cloud server provider is. I think the biggest difference I've seen so far is the concept of providing a large set of services for the front end client to process. the front end, I'm assuming is predominantly web or web app development. As most browsers can handle LAMP vs Microsoft stack well enough, then you are still back to whatever your flavor of the month is. The only difference I truly am seeing from what I did 20 years ago in a highly distributed network environment are higher level protocol (HTTP vs. TCP/UDP). Maybe I am wrong and would welcome the education, but then again I've been doing this a long time and still have not seen anything I would consider revolutionary or significantly different, though languages like Java, C#, Python, Ruby, etc are significantly simpler to program in which is a mixed bag as the bar is lowered for those are are not familiar with writing optimized code. PAAS and SAAS to me seem to be some of the keys in the new technology, but been doing some of this to off and on for 20 years :)

In my case the solution was to remove the compiled framework from the Embedded Binaries, which was a standalone project in the workspace, clean and rebuild it, and finally re-add to Embedded Binaries.

Use System.Data namespace then you will get .AsEnumerable().

I would be careful when using Guava's ComparisonChain because it creates an instance of it per element been compared so you would be looking at a creation of N x Log N comparison chains just to compare if you are sorting, or N instances if you are iterating and checking for equality.

I would instead create a static Comparator using the newest Java 8 API if possible or Guava's Ordering API which allows you to do that, here is an example with Java 8:

import java.util.Comparator;
import static java.util.Comparator.naturalOrder;
import static java.util.Comparator.nullsLast;

private static final Comparator<Person> COMPARATOR = Comparator
  .comparing(Person::getName, nullsLast(naturalOrder()))
  .thenComparingInt(Person::getAge);

@Override
public int compareTo(@NotNull Person other) {
  return COMPARATOR.compare(this, other);
}

Here is how to use the Guava's Ordering API: https://github.com/google/guava/wiki/OrderingExplained

$date = strtotime('2016-2-3');
$date = date('l', $date);
var_dump($date)

(i added format 'l' so it will return full name of day)

Here's the updated FIDDLE

Your HTML should look like this (I only added the button):

<a class="fragment" href="google.com">
    <button id="closeButton">close</button>
    <div>
        <img src ="http://placehold.it/116x116" alt="some description"/> 
        <h3>the title will go here</h3>
        <h4> www.myurlwill.com </h4>
        <p class="text">
        this is a short description yada yada peanuts etc this is a short description yada yada peanuts etc this is a short description yada yada peanuts etc this is a short description yada yada peanuts etcthis is a short description yada yada peanuts etc 
        </p>
    </div>
</a>

and you should add the following CSS:

.fragment {
    position: relative;
}
#closeButton {
    position: absolute;
    top: 0;
    right: 0;
}

Then, to make the button actually work, you should add this javascript:

document.getElementById('closeButton').addEventListener('click', function(e) {
    e.preventDefault();
    this.parentNode.style.display = 'none';
}, false);

We're using e.preventDefault() here to prevent the anchor from following the link.

For a linux env, read the /proc/net/tcp, the second (localaddress) and third (remoteaddress) will give the IPs at hexa format.

Tip: If second column is zeroed (00000000:0000) so its a Listen Port :)

https://github.com/romol0s/python/blob/master/general/functions/getTcpListenIpsByPort.py

https://www.kernel.org/doc/Documentation/networking/proc_net_tcp.txt

I Dont Knew Which one Is Optimized (compared to @AdaTheDev ) but This one seems to be quicker when I use (atleast for me)

SELECT id  FROM  table_1 EXCEPT SELECT DISTINCT (table1_id) table1_id FROM table_2

If You want to get any other specific attribute you can use:

SELECT COUNT(*) FROM table_1 where id in (SELECT id  FROM  table_1 EXCEPT SELECT DISTINCT (table1_id) table1_id FROM table_2);

The given answers work if you're in a context where conda is in your PATH environment variable, e.g. if you set it up that way during installation, or if you're running the "Anaconda Prompt".

If that's not the case, e.g. if you're trying to locate conda for use in a script, you should be able to pick up its installation location by probing HKCU\Software\Python for available Python installations. For example:

>for /F "tokens=2,*" %a in ('reg query HKCU\Software\Python /f InstallPath /s /k /ve ^| findstr Default') do @echo %b
C:\Users\<username>\Miniconda3
C:\Users\<username>\Miniconda3

I tried this code. it's worked for me.

NSMutableString * myString=[[NSMutableString alloc]init];
myString=[myString stringByAppendingString:@"first value"];
myString=[myString stringByAppendingString:@"second string"];

1) In Laravel 5 , form helper is removed .You need to first install laravel collective .

Refer link: https://laravelcollective.com/docs/5.1/html

{!! Form::open(array('route' => 'log_in')) !!}

OR

{!! Form::open(array('route' => '/')) !!}

2) For laravel 4, form helper is already there

{{ Form::open(array('url' => '/')) }}

Make sure you have the Visual C++ Redistributable package installed on your machine.

If you need to get the generic type of a returned type, I used this approach when I needed to find methods in a class which returned a Collection and then access their generic types:

import java.lang.reflect.Method;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.util.Collection;
import java.util.List;

public class Test {

    public List<String> test() {
        return null;
    }

    public static void main(String[] args) throws Exception {

        for (Method method : Test.class.getMethods()) {
            Class returnClass = method.getReturnType();
            if (Collection.class.isAssignableFrom(returnClass)) {
                Type returnType = method.getGenericReturnType();
                if (returnType instanceof ParameterizedType) {
                    ParameterizedType paramType = (ParameterizedType) returnType;
                    Type[] argTypes = paramType.getActualTypeArguments();
                    if (argTypes.length > 0) {
                        System.out.println("Generic type is " + argTypes[0]);
                    }
                }
            }
        }

    }

}

This outputs:

Generic type is class java.lang.String

For those using newer versions Chart.js, you can set a label by setting the callback for tooltips.callbacks.label in options.

Example of this would be:

var chartOptions = {
    tooltips: {
        callbacks: {
            label: function (tooltipItem, data) {
                return 'label';
            }
        }
    }
}

This worked for me on Windows 8.1 and Windows 10.

git config --global mergetool.meld.path "/c/Program Files (x86)/meld/meld.exe"

1. Set var step=1 as global variable by putting it above the function call
2. put semicolons

It will look like this

<head>
<script type="text/javascript">
var image1 = new Image()
image1.src = "images/pentagg.jpg"
var image2 = new Image()
image2.src = "images/promo.jpg"
</script>
</head>
<body>
<p><img src="images/pentagg.jpg" width="500" height="300" name="slide" /></p>
<script type="text/javascript">
        var step=1;
        function slideit()
        {
            document.images.slide.src = eval("image"+step+".src");
            if(step<2)
                step++;
            else
                step=1;
            setTimeout("slideit()",2500);
        }
        slideit();
</script>
</body>

There can be several reasons for this error message:

• Several processes have the database open at the same time (see the FAQ).

• There is a plugin to compress and encrypt the database. It doesn't allow to modify the DB.

• Lastly, another FAQ says: "Make sure that the directory containing the database file is also writable to the user executing the CGI script." I think this is because the engine needs to create more files in the directory.

• The whole filesystem might be read only, for example after a crash.

• On Unix systems, another process can replace the whole file.

You can either use the readonly or the disabled attribute. Note that when disabled, the input's value will not be submitted when submitting the form.

<input id="price_to" value="price to" readonly="readonly">
<input id="price_to" value="price to" disabled="disabled">

You guess correctly. Read the manual page for move_uploaded_file. Set the second parameter to whereever your want to save the file.

If it doesn't work, there is something wrong with your $fileName. Please post your most recent code.

You can use grep:

grep -o "+\S\+" in.txt | tr '\n' ','

which finds the string starting with +, followed by any string \S\+, then convert new line characters into commas. This should be pretty quick for large files.

I was having the same issue and fixed it by simply adding a dataType = "text" line to my ajax call. Make the dataType match the response you expect to get back from the server (your "insert successful" or "something went wrong" error message).

var list = new List<MyClass>();
var item = list.Find( x => x.GetId() == "TARGET_ID" );

or if there is only one and you want to enforce that something like SingleOrDefault may be what you want

var item = list.SingleOrDefault( x => x.GetId() == "TARGET" );

if ( item == null )
    throw new Exception();

you can just do

select rownum, l.* from student  l where name like %ram%

this assigns the row number as the rows are fetched (so no guaranteed ordering of course).

if you wanted to order first do:

select rownum, l.*
  from (select * from student l where name like %ram% order by...) l;

In my case i have changed the root folder in which the Eclipse project were stored. I have discovered tha when i have runned :

cat .plugins/org.eclip.resources/.projects/<projectname>/.location 

I hit this error and it turned out my connection string was pointing to another database, obviously the table didn't exist there.

I spent a few hours on this and no one else has mentioned to double check your connection string.

Visiting this thread after some period of inactivity, but given that I don't see a thorough answer, here's my two cents.

Breadth-first search will always find the shortest path in an unweighted graph. The graph may be cyclic or acyclic.

See below for pseudocode. This pseudocode assumes that you are using a queue to implement BFS. It also assumes you can mark vertices as visited, and that each vertex stores a distance parameter, which is initialized as infinity.

mark all vertices as unvisited
set the distance value of all vertices to infinity
set the distance value of the start vertex to 0
if the start vertex is the end vertex, return 0
push the start vertex on the queue
while(queue is not empty)   
    dequeue one vertex (we’ll call it x) off of the queue
    if x is not marked as visited:
        mark it as visited
        for all of the unmarked children of x:
            set their distance values to be the distance of x + 1
            if the value of x is the value of the end vertex: 
                return the distance of x
            otherwise enqueue it to the queue
if here: there is no path connecting the vertices

Note that this approach doesn't work for weighted graphs - for that, see Dijkstra's algorithm.

instead of

x <- x[! x %in% c(2,3,5)]

using the packages purrr and magrittr, you can do:

your_vector %<>% discard(~ .x %in% c(2,3,5))

this allows for subsetting using the vector name only once. And you can use it in pipes :)

The following is OK in HTML4, but not in XHTML. Check your editor.

<input type=button value="Submit" />

The accepted answer is great for single renames, but here is a way to rename multiple images that have the same repository all at once (and remove the old images).

If you have old images of the form:

$ docker images
REPOSITORY               TAG                 IMAGE ID            CREATED             SIZE
old_name/image_name_1    latest              abcdefghijk1        5 minutes ago      1.00GB
old_name/image_name_2    latest              abcdefghijk2        5 minutes ago      1.00GB

And you want:

new_name/image_name_1
new_name/image_name_2

Then you can use this (subbing in OLD_REPONAME, NEW_REPONAME, and TAG as appropriate):

OLD_REPONAME='old_name'
NEW_REPONAME='new_name'
TAG='latest'

# extract image name, e.g. "old_name/image_name_1"
for image in $(docker images | awk '{ if( FNR>1 ) { print $1 } }' | grep $OLD_REPONAME)
do \
  OLD_NAME="${image}:${TAG}" && \
  NEW_NAME="${NEW_REPONAME}${image:${#OLD_REPONAME}:${#image}}:${TAG}" && \
  docker image tag $OLD_NAME $NEW_NAME && \
  docker rmi $image:${TAG}  # omit this line if you want to keep the old image
done

Since the question asked for either jQuery or vanilla JS, here's an answer with vanilla JS.

I've added some CSS to the demo below to change the button's font color to red when its aria-expanded is set to true

const button = document.querySelector('button');_x000D_
_x000D_
button.addEventListener('click', () => {_x000D_
  button.ariaExpanded = !JSON.parse(button.ariaExpanded);_x000D_
})

button[aria-expanded="true"] {_x000D_
  color: red;_x000D_
}

<button type="button" aria-expanded="false">Click me!</button>

You're checking the wrong method. Moq requires that you Setup (and then optionally Verify) the method in the dependency class.

You should be doing something more like this:

class MyClassTest
{
    [TestMethod]
    public void MyMethodTest()
    {
        string action = "test";
        Mock<SomeClass> mockSomeClass = new Mock<SomeClass>();

        mockSomeClass.Setup(mock => mock.DoSomething());

        MyClass myClass = new MyClass(mockSomeClass.Object);
        myClass.MyMethod(action);

        // Explicitly verify each expectation...
        mockSomeClass.Verify(mock => mock.DoSomething(), Times.Once());

        // ...or verify everything.
        // mockSomeClass.VerifyAll();
    }
}

In other words, you are verifying that calling MyClass#MyMethod, your class will definitely call SomeClass#DoSomething once in that process. Note that you don't need the Times argument; I was just demonstrating its value.

[edited]

using your comment about productCode (and assuming product code is a String) as reference...

 for(Product p : productList){
        s.put(p.getProductCode() , p);
    }

The reason is that modprobe looks into /lib/modules/$(uname -r) for the modules and therefore won't work with local file path. That's one of differences between modprobe and insmod.

You need to use CreateProcess [ http://msdn.microsoft.com/en-us/library/windows/desktop/ms682425(v=vs.85).aspx ]

For ex:

LPTSTR szCmdline[] = _tcsdup(TEXT("\"C:\Program Files\MyApp\" -L -S")); CreateProcess(NULL, szCmdline, /.../);

I prefer to do it in a more direct fashion. It does not have the Rows but is still has the array of rows.

tblCrm.DefaultView.RowFilter = "customertype = 'new'";

qtytotal = 0;
for (int i = 0; i < tblCrm.DefaultView.Count; i++)
{
    result = double.TryParse(tblCrm.DefaultView[i]["qty"].ToString(), out num);
    if (result == false) num = 0;
    qtytotal = qtytotal + num;
}

labQty.Text = qtytotal.ToString();

I just updated matplotlib to 1.1.0 on my system and it now allows me to save to jpg with savefig.

To upgrade to matplotlib 1.1.0 with pip, use this command:

pip install -U 'http://sourceforge.net/projects/matplotlib/files/matplotlib/matplotlib-1.1.0/matplotlib-1.1.0.tar.gz/download'

EDIT (to respond to comment):

pylab is simply an aggregation of the matplotlib.pyplot and numpy namespaces (as well as a few others) jinto a single namespace.

On my system, pylab is just this:

from matplotlib.pylab import *
import matplotlib.pylab
__doc__ = matplotlib.pylab.__doc__

You can see that pylab is just another namespace in your matplotlib installation. Therefore, it doesn't matter whether or not you import it with pylab or with matplotlib.pyplot.

If you are still running into problem, then I'm guessing the macosx backend doesn't support saving plots to jpg. You could try using a different backend. See here for more information.

Try like this:

select field1, array_to_string(array_agg(field2), ',')
from table1
group by field1;

To all the Functional Programming lovers, here is a somewhat functional approach :)

const getHexColor = (rgbValue) =>
  rgbValue.replace("rgb(", "").replace(")", "").split(",")
    .map(colorValue => (colorValue > 15 ? "0" : "") + colorValue.toString(16))
    .reduce((acc, hexValue) => acc + hexValue, "#")

then use it like:

const testRGB = "rgb(13,23,12)"
getHexColor(testRGB)

Unexpected T_VARIABLE

An "unexpected T_VARIABLE" means that there's a literal $variable name, which doesn't fit into the current expression/statement structure.

1. Missing semicolon

   It most commonly indicates a missing semicolon in the previous line. Variable assignments following a statement are a good indicator where to look:

           ?
    func1()
    $var = 1 + 2;     # parse error in line +2
   

2. String concatenation

   A frequent mishap are string concatenations with forgotten . operator:

                                   ?
    print "Here comes the value: "  $value;
   

   Btw, you should prefer string interpolation (basic variables in double quotes) whenever that helps readability. Which avoids these syntax issues.

   String interpolation is a scripting language core feature. No shame in utilizing it. Ignore any micro-optimization advise about variable . concatenation being faster. It's not.

3. Missing expression operators

   Of course the same issue can arise in other expressions, for instance arithmetic operations:

               ?
    print 4 + 7 $var;
   

   PHP can't guess here if the variable should have been added, subtracted or compared etc.

4. Lists

   Same for syntax lists, like in array populations, where the parser also indicates an expected comma , for example:

                                          ?
    $var = array("1" => $val, $val2, $val3 $val4);
   

   Or functions parameter lists:

                                    ?
    function myfunc($param1, $param2 $param3, $param4)
   

   Equivalently do you see this with list or global statements, or when lacking a ; semicolon in a for loop.

5. Class declarations

   This parser error also occurs in class declarations. You can only assign static constants, not expressions. Thus the parser complains about variables as assigned data:

    class xyz {      ?
        var $value = $_GET["input"];
   

   Unmatched } closing curly braces can in particular lead here. If a method is terminated too early (use proper indentation!), then a stray variable is commonly misplaced into the class declaration body.

6. Variables after identifiers

   You can also never have a variable follow an identifier directly:

                 ?
    $this->myFunc$VAR();
   

   Btw, this is a common example where the intention was to use variable variables perhaps. In this case a variable property lookup with $this->{"myFunc$VAR"}(); for example.

   Take in mind that using variable variables should be the exception. Newcomers often try to use them too casually, even when arrays would be simpler and more appropriate.

7. Missing parentheses after language constructs

   Hasty typing may lead to forgotten opening or closing parenthesis for if and for and foreach statements:

           ?
    foreach $array as $key) {
   

   Solution: add the missing opening ( between statement and variable.

                          ?
    if ($var = pdo_query($sql) {
         $result = …
   

   The curly { brace does not open the code block, without closing the if expression with the ) closing parenthesis first.

8. Else does not expect conditions

        ?
   else ($var >= 0)
   

   Solution: Remove the conditions from else or use elseif.

9. Need brackets for closure

        ?
   function() use $var {}
   

   Solution: Add brackets around $var.

10. Invisible whitespace

    As mentioned in the reference answer on "Invisible stray Unicode" (such as a non-breaking space), you might also see this error for unsuspecting code like:

    <?php
                              ?
    $var = new PDO(...);
    

    It's rather prevalent in the start of files and for copy-and-pasted code. Check with a hexeditor, if your code does not visually appear to contain a syntax issue.

See also

• Search: unexpected T_VARIABLE

I also got the same error. Reason for that I was compiling the project using Maven. I had JAVA_HOME pointing to JDK7 and hence java 1.7 was being used for compilation and when running the project I was using JDK1.5. Changing the below entry in .classpath file or change in the eclipse as in the screenshot resolved the issue.

classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/J2SE-1.5

or change in the run configuarions of eclipse as

Updated for Bootstrap 3.3.4:

This will allow you to have different display text and data value for each element. It will also persist the caret on selection.

JS:

$(".dropdown-menu li a").click(function(){
  $(this).parents(".dropdown").find('.btn').html($(this).text() + ' <span class="caret"></span>');
  $(this).parents(".dropdown").find('.btn').val($(this).data('value'));
});

HTML:

<div class="dropdown">
  <button class="btn btn-default dropdown-toggle" type="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="true">
    Dropdown
    <span class="caret"></span>
  </button>
  <ul class="dropdown-menu" aria-labelledby="dropdownMenu1">
    <li><a href="#" data-value="action">Action</a></li>
    <li><a href="#" data-value="another action">Another action</a></li>
    <li><a href="#" data-value="something else here">Something else here</a></li>
    <li><a href="#" data-value="separated link">Separated link</a></li>
  </ul>
</div>

JS Fiddle Example

Modify build.gradle to put your main class in the manifest:

jar {
    manifest {
        attributes 'Implementation-Title': 'Gradle Quickstart',
                   'Implementation-Version': version,
                   'Main-Class': 'hello.helloWorld'
    }
}

Are you sure you have a column DEPARTEMENT_CODE on your table PS_TBL_DEPARTMENT_DETAILS

More informations about your ERROR

ORA-00904: string: invalid identifier Cause: The column name entered is either missing or invalid. Action: Enter a valid column name. A valid column name must begin with a letter, be less than or equal to 30 characters, and consist of only alphanumeric characters and the special characters $, _, and #. If it contains other characters, then it must be enclosed in d double quotation marks. It may not be a reserved word.

For me I modified both the AppTheme and a value colors.xml Both the colorControlNormal and the colorAccent helped me change the EditText border color. As well as the cursor, and the "|" when inside an EditText.

<style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">
    <!-- Customize your theme here. -->
    <item name="colorControlNormal">@color/yellow</item>
    <item name="colorAccent">@color/yellow</item>
</style>

Here is the colors.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <color name="yellow">#B7EC2A</color>
</resources>

I took out the android:textCursorDrawable attribute to @null that I placed inside the editText style. When I tried using this, the colors would not change.

Device Pixel Ratio == CSS Pixel Ratio

In the world of web development, the device pixel ratio (also called CSS Pixel Ratio) is what determines how a device's screen resolution is interpreted by the CSS.

A browser's CSS calculates a device's logical (or interpreted) resolution by the formula:

For example:

Apple iPhone 6s

• Actual Resolution: 750 x 1334
• CSS Pixel Ratio: 2
• Logical Resolution:

When viewing a web page, the CSS will think the device has a 375x667 resolution screen and Media Queries will respond as if the screen is 375x667. But the rendered elements on the screen will be twice as sharp as an actual 375x667 screen because there are twice as many physical pixels in the physical screen.

Some other examples:

Samsung Galaxy S4

• Actual Resolution: 1080 x 1920
• CSS Pixel Ratio: 3
• Logical Resolution:

iPhone 5s

• Actual Resolution: 640 x 1136
• CSS Pixel Ratio: 2
• Logical Resolution:

Why does the Device Pixel Ratio exist?

The reason that CSS pixel ratio was created is because as phones screens get higher resolutions, if every device still had a CSS pixel ratio of 1 then webpages would render too small to see.

A typical full screen desktop monitor is a roughly 24" at 1920x1080 resolution. Imagine if that monitor was shrunk down to about 5" but had the same resolution. Viewing things on the screen would be impossible because they would be so small. But manufactures are coming out with 1920x1080 resolution phone screens consistently now.

So the device pixel ratio was invented by phone makers so that they could continue to push the resolution, sharpness and quality of phone screens, without making elements on the screen too small to see or read.

Here is a tool that also tells you your current device's pixel density:

http://bjango.com/articles/min-device-pixel-ratio/

Yes, there is a way. Two in fact. In October 2013 jshint added a way to ignore blocks of code like this:

// Code here will be linted with JSHint.
/* jshint ignore:start */
// Code here will be ignored by JSHint.
/* jshint ignore:end */
// Code here will be linted with JSHint.

You can also ignore a single line with a trailing comment like this:

ignoreThis(); // jshint ignore:line

Here's a solution that avoids the (often slow) rbind call:

existingDF <- as.data.frame(matrix(seq(20),nrow=5,ncol=4))
r <- 3
newrow <- seq(4)
insertRow <- function(existingDF, newrow, r) {
  existingDF[seq(r+1,nrow(existingDF)+1),] <- existingDF[seq(r,nrow(existingDF)),]
  existingDF[r,] <- newrow
  existingDF
}

> insertRow(existingDF, newrow, r)
  V1 V2 V3 V4
1  1  6 11 16
2  2  7 12 17
3  1  2  3  4
4  3  8 13 18
5  4  9 14 19
6  5 10 15 20

If speed is less important than clarity, then @Simon's solution works well:

existingDF <- rbind(existingDF[1:r,],newrow,existingDF[-(1:r),])
> existingDF
   V1 V2 V3 V4
1   1  6 11 16
2   2  7 12 17
3   3  8 13 18
4   1  2  3  4
41  4  9 14 19
5   5 10 15 20

(Note we index r differently).

And finally, benchmarks:

library(microbenchmark)
microbenchmark(
  rbind(existingDF[1:r,],newrow,existingDF[-(1:r),]),
  insertRow(existingDF,newrow,r)
)

Unit: microseconds
                                                    expr     min       lq   median       uq       max
1                       insertRow(existingDF, newrow, r) 660.131 678.3675 695.5515 725.2775   928.299
2 rbind(existingDF[1:r, ], newrow, existingDF[-(1:r), ]) 801.161 831.7730 854.6320 881.6560 10641.417

Benchmarks

As @MatthewDowle always points out to me, benchmarks need to be examined for the scaling as the size of the problem increases. Here we go then:

benchmarkInsertionSolutions <- function(nrow=5,ncol=4) {
  existingDF <- as.data.frame(matrix(seq(nrow*ncol),nrow=nrow,ncol=ncol))
  r <- 3 # Row to insert into
  newrow <- seq(ncol)
  m <- microbenchmark(
   rbind(existingDF[1:r,],newrow,existingDF[-(1:r),]),
   insertRow(existingDF,newrow,r),
   insertRow2(existingDF,newrow,r)
  )
  # Now return the median times
  mediansBy <- by(m$time,m$expr, FUN=median)
  res <- as.numeric(mediansBy)
  names(res) <- names(mediansBy)
  res
}
nrows <- 5*10^(0:5)
benchmarks <- sapply(nrows,benchmarkInsertionSolutions)
colnames(benchmarks) <- as.character(nrows)
ggplot( melt(benchmarks), aes(x=Var2,y=value,colour=Var1) ) + geom_line() + scale_x_log10() + scale_y_log10()

@Roland's solution scales quite well, even with the call to rbind:

                                                              5       50     500    5000    50000     5e+05
insertRow2(existingDF, newrow, r)                      549861.5 579579.0  789452 2512926 46994560 414790214
insertRow(existingDF, newrow, r)                       895401.0 905318.5 1168201 2603926 39765358 392904851
rbind(existingDF[1:r, ], newrow, existingDF[-(1:r), ]) 787218.0 814979.0 1263886 5591880 63351247 829650894

Plotted on a linear scale:

And a log-log scale:

this works for me:

table {
    border-collapse: collapse;
    border-style: hidden;
}

table td, table th {
    border: 1px solid black;
}

view example ...

tested in FF 3.6 and Chromium 5.0, IE lacks support; from W3C:

Borders with the 'border-style' of 'hidden' take precedence over all other conflicting borders. Any border with this value suppresses all borders at this location.

I found another set of examples for customizing an AlertDialog from a guy named Mossila. I think they're better than Google's examples. To quickly see Google's API demos, you must import their demo jar(s) into your project, which you probably don't want.

But Mossila's example code is fully self-contained. It can be directly cut-and-pasted into your project. It just works! Then you only need to tweak it to your needs. See here

Solved it. So by default, all packages that falls under @SpringBootApplication declaration will be scanned.

Assuming my main class ExampleApplication that has @SpringBootApplication declaration is declared inside com.example.something, then all components that falls under com.example.something is scanned while com.example.applicant will not be scanned.

So, there are two ways to do it based on this question. Use

@SpringBootApplication(scanBasePackages={
"com.example.something", "com.example.application"})

That way, the application will scan all the specified components, but I think what if the scale were getting bigger ?

So I use the second approach, by restructuring my packages and it worked ! Now my packages structure became like this.

src/
+-- main/
¦   +-- java/
|       +-- com.example/
|       |   +-- Application.java
|       +-- com.example.model/
|       |   +-- User.java
|       +-- com.example.controller/
|       |   +-- IndexController.java
|       |   +-- UsersController.java
|       +-- com.example.service/
|           +-- UserService.java
+-- resources/
    +-- application.properties

There are several good articles on the subject on dev2qa.com site, about Contacts Provider API:

How To Add Contact In Android Programmatically

How To Update Delete Android Contacts Programmatically

How To Get Contact List In Android Programmatically

Contacts are stored in SQLite .db files in bunch of tables, the structure is discussed here: Android Contacts Database Structure

Official Google documentation on Contacts Provider here

NVL and COALESCE are used to achieve the same functionality of providing a default value in case the column returns a NULL.

The differences are:

1. NVL accepts only 2 arguments whereas COALESCE can take multiple arguments
2. NVL evaluates both the arguments and COALESCE stops at first occurrence of a non-Null value.
3. NVL does a implicit datatype conversion based on the first argument given to it. COALESCE expects all arguments to be of same datatype.
4. COALESCE gives issues in queries which use UNION clauses. Example below
5. COALESCE is ANSI standard where as NVL is Oracle specific.

Examples for the third case. Other cases are simple.

select nvl('abc',10) from dual; would work as NVL will do an implicit conversion of numeric 10 to string.

select coalesce('abc',10) from dual; will fail with Error - inconsistent datatypes: expected CHAR got NUMBER

Example for UNION use-case

SELECT COALESCE(a, sysdate) 
from (select null as a from dual 
      union 
      select null as a from dual
      );

fails with ORA-00932: inconsistent datatypes: expected CHAR got DATE

SELECT NVL(a, sysdate) 
from (select null as a from dual 
      union 
      select null as a from dual
      ) ;

succeeds.

More information : http://www.plsqlinformation.com/2016/04/difference-between-nvl-and-coalesce-in-oracle.html

I had same problem. I need show url for a search engine

I use two routes like this

Route::get('buscar/{nom}', 'FrontController@buscarPrd');

Route::post('buscar', function(){

   $bsqd = Input::get('nom');    

   return Redirect::action('FrontController@buscarPrd', array('nom'=>$bsqd));

});

First one used to show url like we want

Second one used by form and redirect to first one

Exceding the maximum value of a long doesnt throw an exception, instead it cicles back. If you do this:

Long.MAX_VALUE + 1

you will notice that the result is the equivalent to Long.MIN_VALUE.

From here: java number exceeds long.max_value - how to detect?

Python 3.x version of Etaoin's answer for completeness:

from tkinter.filedialog import askopenfilename
filename = askopenfilename()

Step 1: Copy the link from the HTTPS

Step 2: in the local repository do

git remote rm origin

Step 2: replace github.com with [email protected] in the copied url

Step 3:

git remote add origin url

Suppose you want to set a pop-up text box for clicking a button lets say bt whose id is button, then code using Toast will somewhat look like this:

Button bt;
bt = (Button) findViewById(R.id.button);
bt.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {            
Toast.makeText(getApplicationContext(),"The text you want to display",Toast.LENGTH_LONG)
}