signals/intquit.c

This is signals/intquit.c (Listing 20-2, page 401), an example from the book, The Linux Programming Interface.

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Function list (Bold in this list means a function is not static)

sigHandler()
main()

#include <signal.h>
#include "tlpi_hdr.h"

static void
sigHandler(int sig)
{
    static int count = 0;

    /* UNSAFE: This handler uses non-async-signal-safe functions
       (printf(), exit(); see Section 21.1.2) */

    if (sig == SIGINT) {
        count++;
        printf("Caught SIGINT (%d)\n", count);
        return;                 /* Resume execution at point of interruption */
    }

    /* Must be SIGQUIT - print a message and terminate the process */

    printf("Caught SIGQUIT - that's all folks!\n");
    exit(EXIT_SUCCESS);
}

int
main(int argc, char *argv[])
{
    /* Establish same handler for SIGINT and SIGQUIT */

    if (signal(SIGINT, sigHandler) == SIG_ERR)
        errExit("signal");
    if (signal(SIGQUIT, sigHandler) == SIG_ERR)
        errExit("signal");

    for (;;)                    /* Loop forever, waiting for signals */
        pause();                /* Block until a signal is caught */
}

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