KeboardInterrupt return code value

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21

When a script exits due to an unhandled KeyboardInterrupt, the following function in “Modules/main.c” is called:

static int
exit_sigint(void)
{
    /* bpo-1054041: We need to exit via the
     * SIG_DFL handler for SIGINT if KeyboardInterrupt went unhandled.
     * If we don't, a calling process such as a shell may not know
     * about the user's ^C.  https://www.cons.org/cracauer/sigint.html */
#if defined(HAVE_GETPID) && defined(HAVE_KILL) && !defined(MS_WINDOWS)
    if (PyOS_setsig(SIGINT, SIG_DFL) == SIG_ERR) {
        perror("signal");  /* Impossible in normal environments. */
    } else {
        kill(getpid(), SIGINT);
    }
    /* If setting SIG_DFL failed, or kill failed to terminate us,
     * there isn't much else we can do aside from an error code. */
#endif  /* HAVE_GETPID && !MS_WINDOWS */
#ifdef MS_WINDOWS
    /* cmd.exe detects this, prints ^C, and offers to terminate. */
    /* https://msdn.microsoft.com/en-us/library/cc704588.aspx */
    return STATUS_CONTROL_C_EXIT;
#else
    return SIGINT + 128;
#endif  /* !MS_WINDOWS */
}

On POSIX, if your platform supports getpid() and kill(), the interpreter should exit using the default handler for SIGINT, else it should exit equivalently to calling sys.exit(signal.SIGINT + 128). Try the following:

import os
import signal

signal.signal(signal.SIGINT, signal.SIG_DFL)
os.kill(os.getpid(), signal.SIGINT)
1 Like
22

Thank you Eryk and all those who replied in this thread, the information you provided helped to solve the issue. It was a system configuration related issue, We were able to debug it further in exit_sigint as highlighted by Eryk.