CodeSys defer SIGRT&co demo for "Rauch"
Posted by Anonymous on Thu 17th Jan 2019 08:44
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view followups (newest first): CodeSys defer SIGRT&co demo for Fa. "Rauch" by Anonymous

#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <signal.h>
#include <errno.h>

/* Simple error handling functions */

#define handle_error_en(en, msg) \
        do { errno = en; perror(msg); exit(EXIT_FAILURE); } while (0)


int main(int ac, char *av[])
{
        sigset_t set;
        int i;
        char buff[512];

        (void)puts("#start");

        sigemptyset(&set);
        sigaddset(&set, SIGRTMIN+2);
        sigaddset(&set, SIGRTMIN+3);
        i = pthread_sigmask(SIG_BLOCK, &set, NULL);
        if (i != 0)
                handle_error_en(i, "pthread_sigmask() failed");

        (void)puts("#mark1");

        /*
         * stupid /bin/kill in Linux cannot handle realtime signal
         * *names*, so we pass the signal number instead
         */
        (void)snprintf(buff, sizeof(buff), "kill -s %d %d", SIGRTMIN+2, getpid());
        (void)printf("# executing %s\n", buff);
        (void)system(buff);

        (void)puts("#mark2");

        (void)sleep(2);
        (void)puts("#mark3");

        i = pthread_sigmask(SIG_UNBLOCK, &set, NULL);
        if (i != 0)
                handle_error_en(i, "pthread_sigmask() failed");

        /*
         * unblocking the SIGRTMIN signals will trigger the default handler for
         * the SIGRT signals, which terminates the process, so we will never reach
         * this point in the program
         */
        (void)puts("#notreached");

        return EXIT_SUCCESS;
}