Stopping python using ctrl c

Question

I have a python script that uses threads and makes lots of HTTP requests  I think what s happening is that while a HTTP request  using urllib2  is reading  it s blocking and not responding to CtrlC to stop the program  Is there any way around this

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You can open your task manager  ctrl   alt   delete  then go to task manager  and look through it for python and the server is called  for the example   go app  naming convention is   language app    If I end the  go app task it ll end the server  so going there in the browser will say it  unexpectedly ended   I also use git bash  and when I start a server  I cannot break out of the server in bash s shell with ctrl   c or ctrl   pause  but once you end the python task  the one using 63 7 mb  it ll break out of the server script in bash  and allow me to use the git bash shell

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Forcing the program to close using Alt F4  shuts down current program  Spamming the X button on CMD for e x  Taskmanager  first Windows R and then  taskmgr   and then end the task    Those may help

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The interrupt process is hardware and OS dependent  So you will have very different behavior depending on where you run your python script  For example  on Windows machines we have Ctrl C  SIGINT  and Ctrl Break  SIGBREAK     So while SIGINT is present on all systems and can be handled and caught  the SIGBREAK signal is Windows specific  and can be disabled in CONFIG SYS  and is really handled by the BIOS as an interrupt vector INT 1Bh  which is why this key is much more powerful than any other  So if you re using some  nix flavored OS  you will get different results depending on the implementation  since that signal is not present there  but others are  In Linux you can check what signals are available to you by      kill -l  1  SIGHUP       2  SIGINT       3  SIGQUIT      4  SIGILL       5  SIGTRAP  6  SIGABRT      7  SIGEMT       8  SIGFPE       9  SIGKILL     10  SIGBUS 11  SIGSEGV     12  SIGSYS      13  SIGPIPE     14  SIGALRM     15  SIGTERM 16  SIGURG      17  SIGSTOP     18  SIGTSTP     19  SIGCONT     20  SIGCHLD 21  SIGTTIN     22  SIGTTOU     23  SIGIO       24  SIGXCPU     25  SIGXFSZ 26  SIGVTALRM   27  SIGPROF     28  SIGWINCH    29  SIGPWR      30  SIGUSR1 31  SIGUSR2     32  SIGRTMAX   So if you want to catch the CTRL BREAK signal on a linux system you ll have to check to what POSIX signal they have mapped that key  Popular mappings are   CTRL         SIGQUIT  CTRL D       SIGQUIT CTRL C       SIGINT CTRL Z       SIGTSTOP  CTRL BREAK   SIGKILL or SIGTERM or SIGSTOP   In fact  many more functions are available under Linux  where the SysRq  System Request  key can take on a life of its own

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On Windows  the only sure way is to use CtrlBreak  Stops every python script instantly    Note that on some keyboards   Break  is labeled as  Pause

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Pressing Ctrl   c while a python program is running will cause python to raise a KeyboardInterrupt exception   It s likely that a program that makes lots of HTTP requests will have lots of exception handling code   If the except part of the try-except block doesn t specify which exceptions it should catch  it will catch all exceptions including the KeyboardInterrupt that you just caused   A properly coded python program will make use of the python exception hierarchy and only catch exceptions that are derived from Exception    This is the wrong way to do things try     Some stuff might raise an IO exception except     Code that ignores errors   This is the right way to do things try     Some stuff might raise an IO exception except Exception     This won t catch KeyboardInterrupt   If you can t change the code  or need to kill the program so that your changes will take effect  then you can try pressing Ctrl   c rapidly   The first of the KeyboardInterrupt exceptions will knock your program out of the try block and hopefully one of the later KeyboardInterrupt exceptions will be raised when the program is outside of a try block

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Capture the KeyboardInterrupt  which is launched by pressing ctrl c  and force the exit  from sys import exit  try        Your code     command   input  Type your command      except KeyboardInterrupt        User interrupt the program with ctrl c     exit

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Ctrl D Difference for Windows and Linux It turns out that as of Python 3 6  the Python interpreter handles Ctrl C differently for Linux and Windows  For Linux  Ctrl C would work mostly as expected however on Windows Ctrl C mostly doesn t work especially if Python is running blocking call such as thread join or waiting on web response  It does work for time sleep  however  Here s the nice explanation of what is going on in Python interpreter  Note that Ctrl C generates SIGINT  Solution 1  Use Ctrl Break or Equivalent Use below keyboard shortcuts in terminal console window which will generate SIGBREAK at lower level in OS and terminate the Python interpreter  Mac OS and Linux Ctrl Shift  lt  kbd gt  or Ctrl  lt  kbd gt  Windows   General  Ctrl Break Dell  Ctrl Fn F6 or Ctrl Fn S Lenovo  Ctrl Fn F11 or Ctrl Fn B HP  Ctrl Fn Shift Samsung  Fn Esc  Solution 2  Use Windows API Below are handy functions which will detect Windows and install custom handler for Ctrl C in console   win ctrl c py  import sys  def handler a b None       sys exit 1  def install handler        if sys platform     quot win32 quot           import win32api         win32api SetConsoleCtrlHandler handler  True   You can use above like this  import threading import time import win ctrl c    do something that will block def work        time sleep 10000          t   threading Thread target work  t daemon   True t start     install handler install handler      now block t join     Ctrl C works now   Solution 3  Polling method I don t prefer or recommend this method because it unnecessarily consumes processor and power negatively impacting the performance      import threading     import time      def work            time sleep 10000              t   threading Thread target work      t daemon   True     t start       while True           t join 0 1   100ms   typical human response       you will get KeyboardIntrupt exception

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On a mac   in Terminal     Show Inspector  right click within the terminal window or Shell  Show Inspector  click the Settings icon above  running processes  choose from the list of options under  Signal Process Group   Kill  terminate  interrupt  etc

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For the record  what killed the process on my Raspberry 3B   running raspbian  was Ctrl    On my French AZERTY keyboard  the touch   is also number 4

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This post is old but I recently ran into the same problem of Ctrl C not terminating Python scripts on Linux  I used Ctrl    SIGQUIT

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If it is running in the Python shell use Ctrl   Z  otherwise locate the python process and kill it

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On Mac press Ctrl   to quit a python process attached to a terminal

[python] Stopping python using ctrl+c

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