How to stop/terminate a python script from running?

Question

I wrote a program in IDLE to tokenize text files and it starts to tokeniza 349 text files! How can I stop it? How can I stop a running Python program?

Answer 1

You can also do it if you use the exit() function in your code. More ideally, you can do sys.exit(). sys.exit() which might terminate Python even if you are running things in parallel through the multiprocessing package.

Note: In order to use the sys.exit(), you must import it: import sys

Answer 2

To stop your program, just press Control + C.

Answer 3

If your program is running at an interactive console, pressing CTRL + C will raise a KeyboardInterrupt exception on the main thread.

If your Python program doesn't catch it, the KeyboardInterrupt will cause Python to exit. However, an except KeyboardInterrupt: block, or something like a bare except:, will prevent this mechanism from actually stopping the script from running.

Sometimes if KeyboardInterrupt is not working you can send a SIGBREAK signal instead; on Windows, CTRL + Pause/Break may be handled by the interpreter without generating a catchable KeyboardInterrupt exception.

However, these mechanisms mainly only work if the Python interpreter is running and responding to operating system events. If the Python interpreter is not responding for some reason, the most effective way is to terminate the entire operating system process that is running the interpreter. The mechanism for this varies by operating system.

In a Unix-style shell environment, you can press CTRL + Z to suspend whatever process is currently controlling the console. Once you get the shell prompt back, you can use jobs to list suspended jobs, and you can kill the first suspended job with kill %1. (If you want to start it running again, you can continue the job in the foreground by using fg %1; read your shell's manual on job control for more information.)

Alternatively, in a Unix or Unix-like environment, you can find the Python process's PID (process identifier) and kill it by PID. Use something like ps aux | grep python to find which Python processes are running, and then use kill <pid> to send a SIGTERM signal.

The kill command on Unix sends SIGTERM by default, and a Python program can install a signal handler for SIGTERM using the signal module. In theory, any signal handler for SIGTERM should shut down the process gracefully. But sometimes if the process is stuck (for example, blocked in an uninterruptable IO sleep state), a SIGTERM signal has no effect because the process can't even wake up to handle it.

To forcibly kill a process that isn't responding to signals, you need to send the SIGKILL signal, sometimes referred to as kill -9 because 9 is the numeric value of the SIGKILL constant. From the command line, you can use kill -KILL <pid> (or kill -9 <pid> for short) to send a SIGKILL and stop the process running immediately.

On Windows, you don't have the Unix system of process signals, but you can forcibly terminate a running process by using the TerminateProcess function. Interactively, the easiest way to do this is to open Task Manager, find the python.exe process that corresponds to your program, and click the "End Process" button. You can also use the taskkill command for similar purposes.

Answer 4

• To stop a python script just press Ctrl + C.
• Inside a script with exit(), you can do it.
• You can do it in an interactive script with just exit.
• You can use pkill -f name-of-the-python-script.

Answer 5

To stop a python script using the keyboard: Ctrl + C

To stop it using code (This has worked for me on Python 3) :

import os
os._exit(0)

you can also use:

import sys
sys.exit()

or:

exit()

or:

raise SystemExit

Answer 6

To stop a running program, use Ctrl+C to terminate the process.

To handle it programmatically in python, import the sys module and use sys.exit() where you want to terminate the program.

import sys
sys.exit()

Answer 7

Ctrl-Break it is more powerful than Ctrl-C

Answer 8

When I have a python script running on a linux terminal, CTRL+\ works. (not CRTL + C or D)

Answer 9

Ctrl+Z should do it, if you're caught in the python shell. Keep in mind that instances of the script could continue running in background, so under linux you have to kill the corresponding process.

Answer 10

exit() will kill the Kernel if you're in Jupyter Notebook so it's not a good idea. raise command will stop the program.

Answer 11

To stop your program, just press CTRL + D

or exit().

Answer 12

If you are working with Spyder, use CTRL+. and you will restart the kernel, also you will stop the program.

Answer 13

you can also use the Activity Monitor to stop the py process

Answer 14

Control+D works for me on Windows 10. Also, putting exit() at the end also works.

Answer 15

Windows solution: Control + C.

Macbook solution: Control (^) + C.

Another way is to open a terminal, type top, write down the PID of the process that you would like to kill and then type on the terminal: kill -9 <pid>

Answer 16

Try using:

Ctrl + Fn + S

or

Ctrl + Fn + B

Answer 17

Press Ctrl+Alt+Delete and Task Manager will pop up. Find the Python command running, right click on it and and click Stop or Kill.

Answer 18

I might be a little too late to respond but if you're finding it hard to use sys.exit() or exit() and want to kill the python script from within, this might be helpful

import os
import sys
os.system(F"pkill -f {sys.argv[0]}")

Sometimes, in a really long script with many simultaneous threads, it is difficult to kill just with sys.exit but this works like a charm.

Answer 19

If you are writing a script to process 349 files, but want to test with fewer, just write a nonexisting word like 'stop' in your list, which will cause a stop in the form of an exception. This avoids dialogs like do you want to kill your process if you use exit() or quit()