I start Django server with python manage.py runserver and then quit with CONTROL-C, but I can still access urls in ROOT_URLCONF, why?
Probably you left another process running somewhere else.
Here is how you can list all processes whose command contains manage.py:
ps ax | grep manage.py
Here is how you can kill them:
pkill -f manage.py
Without seeing your script, I would have to say that you have blocking calls, such as socket.recv() or os.system(executable) running at the time of the CTRL+C.
Your script is stuck after the CTRL+C because python executes the KeyboardInterrupt AFTER the the current command is completed, but before the next one. If there is a blocking function waiting for a response, such as an exit code, packet, or URL, until it times out, you're stuck unless you abort it with task manager or by closing the console.
In the case of threading, it kills all threads after it completes its current command. Again, if you have a blocking call, the thread will not exit until it receives its response.
just type exit(), that is what I did and it worked
Related
Got a script for activating a python venv and running a server in the background, but right now I am trying to keep the pid when I start the process and then kill the process with pid after I am done. However, it is not all the time is gets killed.
My question is, can I run the process with a name, then killing it by using pkill name after? and how will that look
#!/bin/sh
ROOT_DIR=$(pwd)
activate(){
source $ROOT_DIR/.venv/bin/activate
python3 src/server.py -l & pid=$! # <== This is the process
python3 src/client.py localhost 8080
}
activate
sleep 10
kill "$pid"
printf "\n\nServer is done, terminating processes..."
You can run programs with a specific command name by using the bash buildin exec. Note that exec replaces the shell with the command so you have to run it in a subshell environment like:
( exec -a my_new_name my_old_command ) &
However, it probably won't help you much because this sets the command line name, which is apparently different from the command name. So executing the above snippet will show your process as "my_new_name" for example in top or htop, but pkill and killall are filtering by the command name and will thus not find a process called "my_new_name".
While it is interesting, how one can start a command with a different name than the executable, it is most likely not the cause of your problem. PIDs never change, so I assume that the problem lays somewhere different.
My best guess is that the server binds a socket to listen on a specific port. If the program is not shutdown gracefully but killed the port number remains occupied and is only freed by the kernel after some time during some kind of kernel garbage collect. If the program is restarted after a short period of time it finds the port already been occupied and prints a misleading message, that says it is already running. If that is indeed the cause of your problem I would strongly consider implementing a way to graceful shutdown the server. (may be already closing the socket in a destructor or something similar could help)
I think you should have to use systemd for this case:
https://github.com/torfsen/python-systemd-tutorial
I am running a simple Flask application on Ubuntu 14 with (I believe) Python 2.7 (having difficulties with 3.x in the virtualenv). Every time I try to close my application with CTRL+C, it launches the app again immediately. If I close it again, it exits, but leaves one process running I can see with ps -a.
If I then run the .py file again, it starts up, then if I exit with CTRL+C, it throws socket.error: [Errno 98] Address already in use and exits.
At this point there are two processes visible with ps -a. Any subsequent startups immediately throw the socket.error.
I have noticed this error is only present when the line app.run(host='0.0.0.0') is left in (changing the IP has no effect).
I am unsure why, and looking for any help into the matter.
Shell
Code
Use
app.run(host=‘0.0.0.0’, debug=True)
instead of
app.run(debug=True)
app.run(host=‘0.0.0.0’)
The latter should start 2 apps continuously.
So when you hit ctrl+C the first time, you are actually terminating the first line, but immediately after that the second line executes and another app starts.
Is there any way to kill a program that ignores all exceptions? Stupid, I know. I was testing something (since I wasn't sure what error a failed, embedded pig script would throw), forgot to limit the loop to a single day, and now it's just continuously running even though I used
ps -ef
to find and directly kill it. I would just let it run to completion since it will definitely terminate, but it runs hadoop jobs, and is needlessly using up resources/popping up on the terminal in between other tasks randomly. I'd like to avoid shutting my desktop down since I'm running other tasks, but will if it'll kill it...
I got the pid from
ps -ef
and used
kill -9
to directly kill it. It no longer shows up when I run
ps -ef | grep
but when I leave my terminal sitting for a little bit (even a new window) these "ghost" hadoop jobs show up that correspond to where the killed task would be.
Normally your Python program would need registered listeners to handle any kill signal you send it. See here:
https://stackoverflow.com/a/1112350/276949
There is a special kill signal (SIGKILL, denoted by-9) which will kill your process no matter what.
kill -9 <pid>
I ran a simple web server using
python -m simpleHTTPServer 8888 &.
it starts well. Then used ctrl+C to attempt to terminate it, and I go to
http://localhost:8888/
and the server is still running. Am I doing something wrong?
I am using zsh for terminal, not sure if this has anything to do with it.
It’s because of the & that causes the command to be run in background. After you started the process, you get the process id. Using that id, you can kill the process:
$ python &
[1] 5050
$ kill -15 5050
[1]+ Angehalten python
If sending a SIGTERM signal (-15) does not work, you can use SIGKILL (-9).
Edited to use SIGTERM instead of SIGKILL, see #starrify’s comment.
CTRL+C sends SIGINT. You should send a kill signal using kill -9 pid to kill the process
I don't know whether you need &. here. However in most of the shells (of course zsh is included) the symbol & mean to start this task in the background, which means your CTRL+C is actually not received by the application.
Try remove the &. and see what would happen.
EDITED: See #RobinKrahl's answer for how to terminate the process by sending a signal to it using kill. However for terminating a finely working process I suggest use SIGTERM (signal number 15) instead of SIGKILL (signal number 9).
It's because of &. It is now a background process which you cannot kill by ctrl+c.
As it is server, I recommend you to use &. To kill off the server, do -> ps aux | grep simpleHTTPServer to find the process id and then do kill -9 pid
TLDR: If sending a SIGKILL doesn't work, as a last resort try killall python
I ran into a similar problem in which the localhost server would simply change to another pid even after I gave it a SIGKILL. The only thing that worked for me, and would probably work as a last resort for anyone else experiencing this would be to simply run in bash: killall python.
I'm trying to start a remote service with fabric and as pointed by this question my command is:
sudo('service jboss start', pty=False)
but unfortunately this command hangs on my terminal and I'm not able to close the fabric command, even with CTRL+C.
The only way I could find to workarround this issue is with a timeout option but if I have more tasks after that they don't run because the timeout is raised and the fab process is exited with an error.
Am I doing something wrong?
It's most likely related to these two FAQ points:
http://docs.fabfile.org/en/1.7/faq.html#init-scripts-don-t-work
http://docs.fabfile.org/en/1.7/faq.html#why-can-t-i-run-programs-in-the-background-with-it-makes-fabric-hang