On Feb 17, 8:46 pm, Philip Winston <pwins...@gmail.com> wrote: > We have a multiprocess Python program that uses Queue to communicate > between processes. Recently we've seen some errors while blocked > waiting on Queue.get: > > IOError: [Errno 4] Interrupted system call > > What causes the exception? Is it necessary to catch this exception > and manually retry the Queue operation? Thanks. >
The exception is caused by a syscall returning EINTR. A syscall will return EINTR when a signal arrives and interrupts whatever that syscall was trying to do. Typically a signal won't interrupt the syscall unless you've installed a signal handler for that signal. However, you can avoid the interruption by using `signal.siginterrupt` to disable interruption on that signal after you've installed the handler. As for the other questions - I don't know, it depends how and why it happens, and whether it prevents your application from working properly. Jean-Paul -- http://mail.python.org/mailman/listinfo/python-list
