On a linux box I've got a python script that's always started from predefined user. It may take a while for it to finish so I want to allow other users to stop it from the web.
Using kill fails with Operation not permitted. 
Can I somehow modify my long running python script so that it'll recive a signal from another user? Obviously, that another user is the one that starts a web server.
May be there's entirely different way to approach this problem I can't think of right now.
You could use sudo to perform the kill command as root, but that is horrible practice.
How about having the long-running script check some condition every x seconds, for example the existence of a file like /tmp/stop-xyz.txt? If that file is found, the script terminates itself immediately.  
(Or any other means of inter-process communication - it doesn't matter.)
terminate script of another user