Questions Tagged with #Operating system

An operating System (OS) is a basic software whose role is to be an abstract layer between software requisitions for resources and the hardware available, manage input/output, memory allocation/deallocation, file systems, among other basic tasks a device (not necessarily a computer) should do.

How do I set a Windows scheduled task to run in the background?

Does anyone know how to set a scheduled task to run in background using Windows Task Scheduler? There doesn't seem to be any option to do this...

What is the difference between the operating system and the kernel?

I do not understand the difference between operating system and kernel. Can someone please explain it?..

What are the differences between virtual memory and physical memory?

I am often confused with the concept of virtualization in operating systems. Considering RAM as the physical memory, why do we need the virtual memory for executing a process? Where does this virtual..

Calculating Waiting Time and Turnaround Time in (non-preemptive) FCFS queue

I have 6 processes as follows: -- P0 -- arrival time = 0 burst time = 10 -- P1 -- arrival time = 110 burst time = 210 -- P2 -- arrival time = 130 burst time = 70 -- P3 -- ar..

Difference between multitasking, multithreading and multiprocessing?

Whats the difference between multitasking, multiprogramming & multiprocessing This comes regularly for my university OS exams and I can't find a good answer. I know quite a bit about multitasking..

How to run regasm.exe from command line other than Visual Studio command prompt?

I want to run regasm.exe from cmd. which is available in c:\windows\\framework\2.057 I do like this c:\ regasm.exe It gives regasm is not recognized as internal or external command. So..

What is the difference between Trap and Interrupt?

What is the difference between Trap and Interrupt? If the terminology is different for different systems, then what do they mean on x86?..

Comprehensive methods of viewing memory usage on Solaris

On Linux, the "top" command shows a detailed but high level overview of your memory usage, showing: Total Memory, Used Memory, Free Memory, Buffer Usage, Cache Usage, Swap size and Swap Usage. My qu..

python: get directory two levels up

Ok...I dont know where module x is, but I know that I need to get the path to the directory two levels up. So, is there a more elegant way to do: import os two_up = os.path.dirname(os.path.dirname(_..

Running windows shell commands with python

How can we interact with OS shell using Python ? I want to run windows cmd commands via python. How can it be achieved ?..

Context.startForegroundService() did not then call Service.startForeground()

I am using Service Class on the Android O OS. I plan to use the Service in the background. The Android documentation states that If your app targets API level 26 or higher, the system imposes..

What is the difference between a process and a thread?

What is the technical difference between a process and a thread? I get the feeling a word like 'process' is overused and there are also hardware and software threads. How about light-weight processes..

What is private bytes, virtual bytes, working set?

I am trying to use the perfmon windows utility to debug memory leaks in a process. This is how perfmon explains the terms: Working Set is the current size, in bytes, of the Working Set of this proce..

Best way to find os name and version in Unix/Linux platform

I need to find the OS name and version on Unix/Linux platform. For this I tried following: lsb_release utility /etc/redhat-release or specific file But it does not seem to be best solution as LSB_..

What is an OS kernel ? How does it differ from an operating system?

I am not able to understand the difference between a kernel and an operating system. I do not see any difference between them. Is the kernel an operating system?..

DNS caching in linux

I am confused about DNS caching. I am writing a small forward proxy server and want to use OS DNS cache on a Linux system. If I understand correctly, then there is DNS caching at the browser level. T..

How to detect my browser version and operating system using JavaScript?

I have tried using the code below but it only display results in Chrome and Mozilla not working in IE6. <div id="example"></div> <script type="text/javascript"> txt = "<p>B..

How is TeamViewer so fast?

Sorry about the length, it's kinda necessary. Introduction I'm developing a remote desktop software (just for fun) in C# 4.0 for Windows Vista/7. I've gotten through basic obstacles: I have a robust..

How to run a program without an operating system?

How do you run a program all by itself without an operating system running? Can you create assembly programs that the computer can load and run at startup, e.g. boot the computer from a flash drive an..

Get operating system info

I recently started wondering about sites like that get the user's operating system info. I have not been able to find out how to do that with PHP, and wanted to try to figure ..

Find Process Name by its Process ID

Suppose I know the process ID. I want to find the process name by its ID, using windows batch script. How can I do this?..

What is the difference between the kernel space and the user space?

What is the difference between the kernel space and the user space? Do kernel space, kernel threads, kernel processes and kernel stack mean the same thing? Also, why do we need this differentiation?..

What is the return value of os.system() in Python?

I came across this: >>> import os >>> os.system('ls') file.txt README 0 What is return value of os.system()? Why I get 0?..

Get Windows version in a batch file

I need to get the OS version with a batch file. I 've seen a lot of examples online, many uses something like this code: @echo off ver | find "XP" > nul if %ERRORLEVEL% == 0 goto ver_xp if not e..

How to uninstall a windows service and delete its files without rebooting

My current project involves deploying an upgraded .exe file that runs as a Windows Service. In order to overwrite the existing .exe with the new version, I currently need to: Stop the service Unins..

What resources are shared between threads?

Recently, I have been asked a question in an interview what's the difference between a process and a thread. Really, I did not know the answer. I thought for a minute and gave a very weird answer. T..

What languages are Windows, Mac OS X and Linux written in?

I was just wondering who knows what programming languages Windows, Mac OS X and Linux are made up from and what languages are used for each part of the OS (ie: Kernel, plug-in architecture, GUI compon..

Fork() function in C

Below is an example of the Fork function in action. Below is also the output. My main question has to to do with the a fork is called how values are changed. So pid1,2 and 3 start off at 0 and get cha..

How can I safely create a nested directory?

What is the most elegant way to check if the directory a file is going to be written to exists, and if not, create the directory using Python? Here is what I tried: import os file_path = "/my/direct..

What are file descriptors, explained in simple terms?

What would be a more simplified description of file descriptors compared to Wikipedia's? Why are they required? Say, take shell processes as an example and how does it apply for it? Does a process ta..

How to find the operating system version using JavaScript?

How can I find the OS name and OS version using JavaScript? ..

How do I check CPU and Memory Usage in Java?

I need to check CPU and memory usage for the server in java, anyone know how it could be done?..

Difference between binary semaphore and mutex

Is there any difference between a binary semaphore and mutex or are they essentially the same?..

What is the difference between user and kernel modes in operating systems?

What are the differences between User Mode and Kernel Mode, why and how do you activate either of them, and what are their use cases?..

Detect Windows version in .net

How can I detect the Windows OS versions in .net? What code can I use?..

Maximum number of processes in linux

What is the maximum limit to the number of processes possible in a linux system? How can we find it ?..

How do I programmatically determine operating system in Java?

I would like to determine the operating system of the host that my Java program is running programmatically (for example: I would like to be able to load different properties based on whether I am on ..

How do I check the operating system in Python?

I want to check the operating system (on the computer where the script runs). I know I can use os.system('uname -o') in Linux, but it gives me a message in the console, and I want to write to a varia..

How to make parent wait for all child processes to finish?

I'm hoping someone could shed some light on how to make the parent wait for ALL child processes to finish before continuing after the fork. I have cleanup code which I want to run but the child proces..

How do I check OS with a preprocessor directive?

I need my code to do different things based on the operating system on which it gets compiled. I'm looking for something like this: #ifdef OSisWindows // do Windows-specific stuff #else // do Unix-sp..

What is the difference between user variables and system variables?

What is the difference between user variables such as PATH, TMP, etc. and system variables? I accidentally deleted the user variable PATH. What am I supposed to do?..

how to display excel sheet in html page

I want to display EXCEL sheet embedded in IE with plain HTML. I have gone through other questions on stackoverflow but could not find any useful one. Here is my html file <html> <body> &..

Python argparse: default value or specified value

I would like to have a optional argument that will default to a value if only the flag is present with no value specified, but store a user-specified value instead of the default if the user specifies..

How to make ng-repeat filter out duplicate results

I'm running a simple ng-repeat over a JSON file and want to get category names. There are about 100 objects, each belonging to a category - but there are only about 6 categories. My current code is ..

How to include file in a bash shell script

Is there a way to include another shell script in a shell script to be able to access its functions? Like how in PHP you can use the include directive with other PHP files in order to run the functio..

Disabling enter key for form

I have been trying to disable the Enter key on my form. The code that I have is shown below. For some reason the enter key is still triggering the submit. The code is in my head section and seems to b..

Inline style to act as :hover in CSS

I know that embedding CSS styles directly into the HTML tags they affect defeats much of the purpose of CSS, but sometimes it's useful for debugging purposes, as in: <p style="font-size: 24px">..

Access properties file programmatically with Spring?

We use the code below to inject Spring beans with properties from a properties file. <bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"> <property name=..

How to implement Enums in Ruby?

What's the best way to implement the enum idiom in Ruby? I'm looking for something which I can use (almost) like the Java/C# enums...

How to convert a string to an integer in JavaScript?

How do I convert a string to an integer in JavaScript?..

Removing leading and trailing spaces from a string

How to remove spaces from a string object in C++. For example, how to remove leading and trailing spaces from the below string object. //Original string: " This is a sample string ..

Convert text to columns in Excel using VBA

I'm trying to convert text to columns using a macro but I'm not able to do it, I have tried to record a macro to achieve this, however I'm running into some issues since the text to columns VBA functi..

How to pass parameters on onChange of html select

I am a novice at JavaScript and jQuery. I want to show one combobox-A, which is an HTML <select> with its selected id and contents at the other place on onChange(). How can I pass the complete..

Convert JSON String to Pretty Print JSON output using Jackson

This is the JSON string I have: {"attributes":[{"nm":"ACCOUNT","lv":[{"v":{"Id":null,"State":null},"vt":"java.util.Map","cn":1}],"vt":"java.util.Map","status":"SUCCESS","lmd":13585},{"nm":"PROFILE","..

How to set adaptive learning rate for GradientDescentOptimizer?

I am using TensorFlow to train a neural network. This is how I am initializing the GradientDescentOptimizer: init = tf.initialize_all_variables() sess = tf.Session() mse = tf.r..

How to prevent column break within an element?

Consider the following HTML: <div class='x'> <ul> <li>Number one</li> <li>Number two</li> <li>Number three</li> <..

Java POI : How to read Excel cell value and not the formula computing it?

I am using Apache POI API to getting values from an Excel file. Everything is working great except with cells containing formulas. In fact, the cell.getStringCellValue() is returning the formula used..

Catch an exception thrown by an async void method

Using the async CTP from Microsoft for .NET, is it possible to catch an exception thrown by an async method in the calling method? public async void Foo() { var x = await DoSomethingAsync(); ..

How to customize a Spinner in Android

I want to add a custom height to the dropdown of a Spinner, say 30dp, and I want to hide the dividers of the dropdown list of Spinner. So far I tried to implement following style to the Spinner: <..

List all kafka topics

I'm using kafka 0.10 without zookeeper. I want to get kafka topics list. This command is not working since we're not using zookeeper: bin/ --list --zookeeper localhost:2181. How can I ..

Eclipse/Java code completion not working

I've downloaded, unzipped and setup Eclipse 3.4.2 with some plugins (noteable, EPIC, Clearcase, QuantumDB, MisterQ). Now I find when I'm editing Java projects the code completion is not working. If..

What is the preferred syntax for defining enums in JavaScript?

What is the preferred syntax for defining enums in JavaScript? Something like: my.namespace.ColorEnum = { RED : 0, GREEN : 1, BLUE : 2 } // later on if(currentColor == my.namespace.Colo..

How to get user agent in PHP

I'm using this JS code to know what browser is user using for. <script> document.write(navigator.appName); </script> And I want to get this navigator.appName to php code to use it li..

VB.NET Connection string (Web.Config, App.Config)

Really having an annoying time with connection strings. I have two projects together in a single solution. A Web forms application acting as the presentation layer, and a class library supporting it ..

How do I change a TCP socket to be non-blocking?

How do you make a socket non-blocking? I am aware of the fcntl() function, but I've heard it's not always reliable...

How to get a jqGrid cell value when editing

How to get a jqGrid cell value when in-line editing (getcell and getRowData returns the cell content and not the actuall value of the input element)...

Android Studio - How to Change Android SDK Path

When I open Android SDK Manager from Android Studio, the SDK Path displayed is: \android-studio\sdk I want to change this path. How do I do it?..

How do you change the value inside of a textfield flutter?

I have a TextEditingController where if a user clicks a button it fills in with information. I can't seem to figure out how to change the text inside of a Textfield or TextFormField. Is there a soluti..

How to see the proxy settings on windows?

Our work laptops are configured to use proxy to access external sites and I don't have access to see the proxy information. All our applications like IDEs are configured to use system proxy. Is there ..

"No Content-Security-Policy meta tag found." error in my phonegap application

After update Cordova 5.0 in my system, I create new applications. When I tested my application on a device that time I get an error in the console log: No Content-Security-Policy meta tag found. Plea..

Setting Custom ActionBar Title from Fragment

In my Main FragmentActivity, I setup my custom ActionBar title like this: LayoutInflater inflator = (LayoutInflater) this .getSystemService(Context.LAYOUT_INFLATER_SERVICE); View ..

What is the purpose of wrapping whole Javascript files in anonymous functions like “(function(){ … })()”?

I have been reading a lot of Javascript lately and I have been noticing that the whole file is wrapped like the following in the .js files to be imported. (function() { ... code ... })()..

Using current time in UTC as default value in PostgreSQL

I have a column of the TIMESTAMP WITHOUT TIME ZONE type and would like to have that default to the current time in UTC. Getting the current time in UTC is easy: postgres=# select now() at time zone '..

What is 0x10 in decimal?

I have the following code: SN.get_Chars(5) SN is a string so this should give the 5th Char. Ok! Now I have another code but: SN.get_Chars(0x10) I wonder what 0x10 is? Is it a number? If it's so, ..

How to get row number in dataframe in Pandas?

How can I get the number of the row in a dataframe that contains a certain value in a certain column using Pandas? For example, I have the following dataframe: ClientID LastName 0 34 ..

jQuery UI: Datepicker set year range dropdown to 100 years

Using the Datepicker the year drop down by default shows only 10 years. The user has to click the last year in order to get more years added. How can we set the initial range to be 100 years so that ..

Should jQuery's $(form).submit(); not trigger onSubmit within the form tag?

I have the following: <script type="text/javascript"> function CancelFormButton(button) { $(button.form).submit(); } </script> <form onsubmit="alert('here');"> <input type="..

Android Studio Run/Debug configuration error: Module not specified

I am getting a 'Module not specified' error in my run config. I have no module showing in the drop down yet I can see my module no probs. The issue came about when I refactored my module name, changed..

jQuery count number of divs with a certain class?

Considering something like this; <div class="wrapper"> <div class="item"></div> <div class="item"></div> <div class="item"></div> <div cla..

How do I get the command-line for an Eclipse run configuration?

I have several JUnit run configurations in Eclipse that I need to replicate on the command-line in order to use a third-party analysis tool. So far I've just been writing the command-line manually by..

How do I mount a host directory as a volume in docker compose

I have a development environment I'm dockerizing and I would like the ability to livereload my changes without having to rebuild docker images. I'm using docker compose because redis is one of my app'..

Fastest way to tell if two files have the same contents in Unix/Linux?

I have a shell script in which I need to check whether two files contain the same data or not. I do this a for a lot of files, and in my script the diff command seems to be the performance bottleneck...

What is the maximum float in Python?

I think the maximum integer in python is available by calling sys.maxint. What is the maximum float or long in Python?..

Invalid character in identifier

I am working on the letter distribution problem from HP code wars 2012. I keep getting an error message that says "invalid character in identifier". What does this mean and how can it be fix..

Bind service to activity in Android

I'm trying to write a simple media player that plays streaming audio using RTSP. I have a GUI-activity and a service that performs the playback. My question is how to best communicate between the acti..

PHP + curl, HTTP POST sample code?

Can anyone show me how to do a php curl with an HTTP POST? I want to send data like this: username=user1, password=passuser1, gender=1 To I expect the curl to return a response lik..

Accessing AppDelegate from framework?

I'm creating my first framework in Objective-C that wraps the facebook SDK in a more intuitive way. There are several points in my framework where I'd like to reference the AppDelegate, but there is n..

How do you load custom UITableViewCells from Xib files?

The question is simple: How do you load custom UITableViewCell from Xib files? Doing so allows you to use Interface Builder to design your cells. The answer apparently is not simple due to memory mana..

Nginx serves .php files as downloads, instead of executing them

I am installing a website in a droplet (Digital Ocean). I have a issue for install NGINX with PHP properly. I did a tutorial

What is the difference between Spring, Struts, Hibernate, JavaServer Faces, Tapestry?

May I know what is the difference between:- Spring Struts Struts 2 Hibernate JavaServer Faces JavaServer Pages Tapestry Are these technologies/framework complementary to each other? Or they are al..

Iterate through string array in Java

I have String array with some components, this array has 5 components and it vary some times. What I would like to do is to iterate through that array and get the first component and the component nex..

How can I check whether an array is null / empty?

I have an int array which has no elements and I'm trying to check whether it's empty. For example, why is the condition of the if-statement in the code below never true? int[] k = new int[3]; if (k..

How to get cell value from DataGridView in VB.Net?

I have a problem, how can i get value from cell of datagridview ---------------------------------- id | p/w | post | ---------------------------------- 1 | 1234 | A ..

Python: Get HTTP headers from urllib2.urlopen call?

Does urllib2 fetch the whole page when a urlopen call is made? I'd like to just read the HTTP response header without getting the page. It looks like urllib2 opens the HTTP connection and then subs..

Why do we usually use || over |? What is the difference?

I'm just wondering why we usually use logical OR || between two booleans not bitwise OR |, though they are both working well. I mean, look at the following: if(true | true) // pass if(true | fals..

Why is ZoneOffset.UTC != ZoneId.of("UTC")?

Why does ZonedDateTime now =; System.out.println(now.withZoneSameInstant(ZoneOffset.UTC) .equals(now.withZoneSameInstant(ZoneId.of("UTC")))); print out false? I would e..

error opening trace file: No such file or directory (2)

I am getting the above error: error opening trace file: No such file or directory (2) when I run my android application on the emulator. Can someone tell me what could be the possible reason f..

What is the difference between __str__ and __repr__?

What is the difference between __str__ and __repr__ in Python?..

/usr/lib/ version `GLIBCXX_3.4.15' not found

How can I get GLIBCXX_3.4.15 in Ubuntu? I can't run some programs that I'm compiling. When I do: strings /usr/lib/ | grep GLIBC I get: GLIBCXX_3.4 GLIBCXX_3.4.1 GLIBCXX_3.4.2 GLIBCX..

How can I access Google Sheet spreadsheets only with Javascript?

I want to access Google Spreadsheets using JavaScript only (no .NET, C#, Java, etc.) I came here and was shocked to know that there is NO API for JavaScript to access Google Sheets. Please tell me h..

Converting java.sql.Date to java.util.Date

What's the simplest way to convert a java.sql.Date object to a java.util.Date while retaining the timestamp? I tried: java.util.Date newDate = new Date(result.getDate("VALUEDATE").getTime()); with..

How to read strings from a Scanner in a Java console application?

import java.util.Scanner; class MyClass { public static void main(String args[]) { Scanner scanner = new Scanner(; int employeeId, supervisorId; String name; ..

Best Java obfuscator?

I am developing a security software and want to obfuscate my java code so it will become impossible to reverse engineer. What is the most reliable java obfuscator ?..

numpy get index where value is true

>>> ex=np.arange(30) >>> e=np.reshape(ex,[3,10]) >>> e array([[ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9], [10, 11, 12, 13, 14, 15, 16, 17, 18, 19], [20, 21, 22, ..

Converting Stream to String and back...what are we missing?

I want to serialize objects to strings, and back. We use protobuf-net to turn an object into a Stream and back, successfully. However, Stream to string and back... not so successful. After going thr..

"unrecognized selector sent to instance" error in Objective-C

I created a button and added an action for it, but as soon as it invoked, I got this error: -[NSCFDictionary numberButtonClick:]: unrecognized selector sent to instance 0x3d03ac0 2010-03-16 22:23:58..

How to check if an NSDictionary or NSMutableDictionary contains a key?

I need to check if an dict has a key or not. How?..

What languages are Windows, Mac OS X and Linux written in?

I was just wondering who knows what programming languages Windows, Mac OS X and Linux are made up from and what languages are used for each part of the OS (ie: Kernel, plug-in architecture, GUI compon..

MySQL Install: ERROR: Failed to build gem native extension

I'm trying to get MySQL installed to the latest version due to some installation going wrong somewhere along the line. I run the command gem install mysql and I receive the following: Building na..

Using regular expressions to do mass replace in Notepad++ and Vim

So I've got a big text file which looks like the following: <option value value='1' >A <option value value='2' >B <option value value='3' >C <option value value='4' >D It's ..

Where can I view Tomcat log files in Eclipse?

Where can I view Tomcat log files in Eclipse? For some reason my Tomcat installation/log folder is always empty. BTW, does Tomcat dump to the log file after a while or is it immediate?..

How to cast or convert an unsigned int to int in C?

My apologies if the question seems weird. I'm debugging my code and this seems to be the problem, but I'm not sure. Thanks!..

Python function overloading

I know that Python does not support method overloading, but I've run into a problem that I can't seem to solve in a nice Pythonic way. I am making a game where a character needs to shoot a variety of..

What is the purpose of Node.js module.exports and how do you use it?

What is the purpose of Node.js module.exports and how do you use it? I can't seem to find any information on this, but it appears to be a rather important part of Node.js as I often see it in source c..

Using custom font in android TextView using xml

I have added a custom font file to my assets/fonts folder. How do I use it from my XML? I can use it from code as follows: TextView text = (TextView) findViewById(; Typeface tf = ..

Is there anything like .NET's NotImplementedException in Java?

Is there anything like .NET's NotImplementedException in Java?..

Can I avoid the native fullscreen video player with HTML5 on iPhone or android?

I've built a web app that uses the HTML5 tag and JavaScript code that renders other content synchronized with the running video. It works great in desktop browsers: Firefox, Chrome, and Safari. On an..

Converting VS2012 Solution to VS2010

I'm working in VB project with VS 2012 and after finish I try to add setup project. I didn't find it (because the Setup Project was discontinued after VS2010) so I switched to VS2010 but the problem..

Clear the cache in JavaScript

How do I clear a browsers cache with JavaScript? We deployed the latest JavaScript code but we are unable to get the latest JavaScript code. Editorial Note: This question is semi-duplicated in the f..

Regular expression: zero or more occurrences of optional character /

What is the regular expression pattern to say: zero or more occurrences of the character / ?..

How to find value using key in javascript dictionary

I have a question about Javascript's dictionary. I have a dictionary in which key-value pairs are added dynamically like this: var Dict = [] var addpair = function (mykey , myvalue) [ Dict.push({ ..

Field 'browser' doesn't contain a valid alias configuration

I've started using webpack2 (to be precise, v2.3.2) and after re-creating my config I keep running into an issue I can't seem to solve I get (sorry in advance for ugly dump): ERROR in ./src/main.js M..

concat scope variables into string in angular directive expression

I am using a scope method in an angular ng-click directive like so: <a ng-click="$navigate.go('#/path/obj.val1/obj.val2')">{{obj.val1}}, {{obj.val2}}</a> The trouble here is that

How to add RSA key to authorized_keys file?

I've created an RSA public key and I want to add that to authorized_keys file, but there is no such file in my Ubuntu 11.10 machine. How can I add the key to authorized_keys?..

get an element's id

Is there another way to get an DOM element's ID? element.getAttribute('id') ..

How do you use subprocess.check_output() in Python?

I have found documentation about subprocess.check_output() but I cannot find one with arguments and the documentation is not very in depth. I am using Python 3 (but am trying to run a Python 2 file t..

http://localhost:8080/ Access Error: 404 -- Not Found Cannot locate document: /

I'm really very new to this Tomcat stuff. I downloaded Tomcat 7.0 windows installer and installed it using the default configuration. After installing, I typed localhost:8080 in my browser to see if T..

Hash Map in Python

I want to implement a HashMap in Python. I want to ask a user for an input. depending on his input I am retrieving some information from the HashMap. If the user enters a key of the HashMap, I would..

Cannot start GlassFish 4.1 from within Netbeans 8.0.1 Service area

On Windows 7 I downloaded the 'netbeans-8.0.1-javaee-windows.exe' installer from this site The installer installs GlassFish 4.1, Java 1.8.0_20 and NetBeans 8.01. After..

'Java' is not recognized as an internal or external command

When trying to check the current version of Java in which I am running, I received the error "java is not recognized as an internal or external command, operable program or batch file.". I a..

How to set Angular 4 background image?

I am trying the following lines to set the background image.but it not works. what are the way set background image in constantly in my application. app.component.html <div [ngStyle]="{'backgroun..

Using Excel VBA to run SQL query

I am fairly new to SQL and VBA. I have written a SQL query that I would like to be able to call and run from a VBA sub in an excel workbook and then bring the query results into the workbook. I have f..

What should my Objective-C singleton look like?

My singleton accessor method is usually some variant of: static MyClass *gInstance = NULL; + (MyClass *)instance { @synchronized(self) { if (gInstance == NULL) gInstance ..

How to pass extra variables in URL with WordPress

I am having trouble trying to pass an extra variable in the url to my WordPress installation. For example /news?c=123 For some reason, it works only on the website root but it..

Should I use window.navigate or document.location in JavaScript?

What's the preferred method to use to change the location of the current web page using JavaScript? I've seen both window.navigate and document.location used. Are there any differences in behavior? Ar..

C++, copy set to vector

I need to copy std::set to std::vector: std::set <double> input; input.insert(5); input.insert(6); std::vector <double> output; std::copy(input.begin(), input.end(), output.begin()); //E..

Automated testing for REST Api

I would like to write an automated testing suite for a REST API. As we complete new services, we'd like to check to make sure all the previously created services are working as expected. Any suggestio..

'cannot open git-upload-pack' error in Eclipse when cloning or pushing git repository

I am not able to clone or push to a git repository at Bitbucket in Eclipse: It's weird, because a day before I didn't have any problem. I have downloaded the sts 3 times with no luck. This error ke..

jQuery validation: change default error message

Is there a simple way to change the default error values in the jQuery validation plugin? I just want to rewrite the error messages to be more personal to my app--I have a lot of fields, so I don't w..

Session TimeOut in web.xml

I am trying to understand the real purpose of session configuration in Web.xml for session timeout. <!-- Session Configuration --> <session-config> <session-timeout>60</s..

Restrict varchar() column to specific values?

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