signalfd() syscall example

signalfd_example.c

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <signal.h>
#include <sys/signalfd.h>

int segv_handle()
{
    printf("segv\n");
    exit(0);
}

int main(void)
{
    int fd;
    sigset_t mask;

    sigemptyset(&mask);
    sigaddset(&mask, SIGQUIT);
    sigaddset(&mask, SIGINT);
    sigaddset(&mask, SIGSEGV);

    if (sigprocmask(SIG_BLOCK, &mask, NULL) < 0) {
        printf("Failed to signalmask\n");
        return -1;
    }

    fd = signalfd(-1, &mask, 0);
    if (fd < 0)
        return -1;

    while (1) {
        struct signalfd_siginfo si;
        int ret;

        ret = read(fd, &si, sizeof(si));
        if (ret < 0)
            return -1;

        if (ret != sizeof(si))
            return -1;

        if (si.ssi_signo == SIGQUIT)
            printf("receive ctrl + \\\n");
        else if (si.ssi_signo == SIGINT)
            printf("receive ctrl + c\n");
        else if (si.ssi_signo == SIGSEGV)
            segv_handle();
    }

    return 0;
}