signals

I want to write a few extra lines to a file when interrupted with ctrl-c before the program dies. However the location of the file is not hard coded so I need something more than normal interrupt handling as explained here . What is the best way to do this? Motivation: I'm doing time dependent finite element simulations. Sometimes I forget or mis-estimate a reasonable tmax and the simulation would take a very long time to complete, so I interrupt it with ctrl-c. However I still want to use the data generated up to that point. In particular there's an xml file which needs a few lines appended

My model post processing is using the post_save signal: from django.core.signals import request_finished from django.dispatch import receiver from models import MyModel from pipeline import this_takes_forever @receiver(post_save, sender=MyModel) def my_callback(sender, **kwargs): this_takes_forever(sender) The this_takes_forever routine does IO so I want to defer it to avoid blocking the request too much. I thought this was a great use case for the new asyncio module. But I have a hard time getting my mind around the whole process. I think I should be able to adapt the signal receiver like

I've seen a lot of questions related to this... but my code works on python 2.6.2 and fails to work on python 2.6.5. Am I wrong in thinking that the whole atexit "functions registered via this module are not called when the program is killed by a signal" thing shouldn't count here because I'm catching the signal and then exiting cleanly? What's going on here? Whats the proper way to do this? import atexit, sys, signal, time, threading terminate = False threads = [] def test_loop(): while True: if terminate: print('stopping thread') break else: print('looping') time.sleep(1) @atexit.register

I was doing a little reading about sigaction() (sources are from my course notes) and I'm not sure I understand this text: The signal mask is calculated and installed only for the duration of the signal handler. By default, the signal “sig” is also blocked when the signal occurs. Once an action is installed for a specific signal using sigaction, it remains installed until another action is explicitly requested. Does this mean that the default signal mask is restored after returning form the signal handler? Also, do I have to re-install the handler after using it, as if I was using signal() ?

Possible Duplicate: Is destructor called if SIGINT or SIGSTP issued? My code like this: #include <iostream> #include <signal.h> #include <cstdlib> void handler(int) { std::cout << "will exit..." << std::endl; exit(0); } class A { public: A() {std::cout << "constructor" << std::endl;} ~A() {std::cout << "destructor" << std::endl;} }; int main(void) { signal(SIGINT, &handler); A a; for (;;); return 0; } When I pressed Ctrl-C, it printed: constructor ^Cwill exit... There is no "destructor" printed. So, how can I exit cleanly? With difficulty. Already, the code you've written has undefined

In this previous question I posted most of my own shell code. My next step is to implement foreground and background process execution and properly wait for them to terminate so they don't stay as "zombies". Before adding the possibility to run them in the background, all processes were running in the foreground. And for that, I simply called wait(NULL) after executing any process with execvp(). Now, I check for the '&' character as the last argument and if it's there, run the process in the background by not calling wait(NULL) and the process can run happily in the background will I'm