Re: Signal SIGINT ignored during socket.accept

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Date	Fri, 11 Sep 2015 04:36:43 +1000
Subject	Re: Signal SIGINT ignored during socket.accept
From	Chris Angelico <rosuav@gmail.com>
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On Fri, Sep 11, 2015 at 4:24 AM, James Harris <james.harris.1@gmail.com> wrote:
> I have a listening socket, self.lsock, which is used in an accept() call as
> follows
>
>  endpoint = self.lsock.accept()
>
> The problem is that if control-C is pressed it is not recognised until
> something connects to that socket. Only when the accept() call returns is
> the signal seen.
>
> The question, then, is how to get the signal to break out of the accept()
> call. This is currently on Windows but I would like it to run on Unix too. I
> see from the web that this type of thing is a common problem with the
> underlying C libraries but I cannot quite relate the posts I have found to
> Python.

What version of Python are you using? Also (in case it matters), what
version of Windows?

Have you tested on any Unix system? I just tried on my Linux, and
Ctrl-C interrupted the accept() straight away, so this is quite
probably a Windows-only issue.

Can you produce an absolute minimal demo program? I'd try something like this:

import socket
s = socket.socket()
s.listen(1)
s.accept()

which is what worked for me (interactively, Python 2.7.9 and 3.6.0a0,
Debian Linux).

ChrisA

Thread

Signal SIGINT ignored during socket.accept "James Harris" <james.harris.1@gmail.com> - 2015-09-10 19:24 +0100
  Re: Signal SIGINT ignored during socket.accept Chris Angelico <rosuav@gmail.com> - 2015-09-11 04:36 +1000
    Re: Signal SIGINT ignored during socket.accept "James Harris" <james.harris.1@gmail.com> - 2015-09-10 20:11 +0100
      Re: Signal SIGINT ignored during socket.accept Chris Angelico <rosuav@gmail.com> - 2015-09-11 05:26 +1000
        Re: Signal SIGINT ignored during socket.accept "James Harris" <james.harris.1@gmail.com> - 2015-09-10 21:12 +0100
          Re: Signal SIGINT ignored during socket.accept Chris Angelico <rosuav@gmail.com> - 2015-09-11 12:01 +1000
            Re: Signal SIGINT ignored during socket.accept Grant Edwards <invalid@invalid.invalid> - 2015-09-11 13:50 +0000
              Re: Signal SIGINT ignored during socket.accept Marko Rauhamaa <marko@pacujo.net> - 2015-09-11 17:00 +0300
              Re: Signal SIGINT ignored during socket.accept Chris Angelico <rosuav@gmail.com> - 2015-09-12 00:27 +1000
              Re: Signal SIGINT ignored during socket.accept "James Harris" <james.harris.1@gmail.com> - 2015-09-11 18:14 +0100
                Re: Signal SIGINT ignored during socket.accept "James Harris" <james.harris.1@gmail.com> - 2015-09-12 00:15 +0100

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