[Zope] System performance threads/proccesses & random crashes (SIGPIPE)

[Chris McDonough]

> A couple of more things:
>
> This, so far as I can tell is a bug in the FastCGI implementation (Not
> handling SIGPIPE as suggested).  Should I report it somewhere?

The bit you passed along from the FastCGI website seems to intimate that the
behavior is expected... I'm not sure where you would report it. ;-)

> Python installs a small number of signal handlers by default: SIGPIPE is
> ignored (so write errors on pipes and sockets can be reported as ordinary
> Python exceptions)

I didn't know this.  It appears Python already installs SIG_IGN as the
signal handler for a SIGPIPE signal... mm.  I'm not sure how your
configuration manages to get around this. I'd have to guess that some
product is resetting the signal handler.

> And finally, how do I "ignore" a signal ? I guess just writing a "pass"
> will work ? I'll try it out, I guess on reception of a signal, only one
> handler is a called once?

import signal
signal.signal(signal.SIGPIPE, signal.SIG_IGN)

This installs a null signal handler for the SIGPIPE signal.

I wonder if you could find the place in the code where the exception occurs
when you click a lot and place a "print signal.getsignal(signal.SIGPIPE)"
right before the place that the error happens.  See if it's 1.  If it's 1...
well, I'm not sure.  I dont know how the process could be killed by a SIGPIE
then.

If it's 0, that means that something has installed a signal handler on top
of Python's default "ignore SIGPIPE" signal handler, and you might be able
to find it by grepping for "SIGPIPE" or "13" in your code.

- C