[Python-Dev] C bindings calling tmpfile() blocks interrupt signal

[Florent Pillet]

I discovered an issue on Mac OS X that seems to relate to signal
handling. I have a C binding in which I call the standard tmpfile()
function. After calling it, I can't break Python anymore with CTRL-C.

Investigating the Darwin source code for tmpfile() (and FreeBSD, they
are the same) , I found that the function is mucking with the signals:

http://www.freebsd.org/cgi/cvsweb.cgi/src/lib/libc/stdio/tmpfile.c?rev=1.9&content-type=text/x-cvsweb-markup

Is this considered a Python issue, or an OS issue? I ran a simple test
against the interrupt signal, which didn't show any wrong behavior:

static void intcatcher(int sig) {
    printf("Interrupt catched\n");
    exit(1);
}
int main(int argc, char **argv) {
    signal(SIGINT, intcatcher);
    printf("Press CTRL-C to interrupt...\n");
    tmpfile();
    while (1)
        ;
    return 0;
}

But with my threaded Python code, SIGINT doesn't work anymore after my
binding has called tmpfile().

Florent

-- 
Florent Pillet                  http://www.florentpillet.com
Freelance software developer/consultant - Palm OS & Mac OS X
ICQ: 117292463                Skype: callto://florent.pillet