Tín hiệu và sigaction

#include <stdio.h>
#include <signal.h>

static volatile sig_atomic_t nen_thoat = 0;

static void xu_ly(int s) {
    (void)s;
    nen_thoat = 1;              /* CHI dat co, khong lam gi khac */
}

int main(void) {
    signal(SIGINT, xu_ly);     /* SIGINT (Ctrl+C) -> goi xu_ly */

    int vong = 0;
    while (!nen_thoat) {
        printf("  vong %d\n", ++vong);
        if (vong == 3) raise(SIGINT);   /* mo phong Ctrl+C */
    }
    printf("da bat tin hieu, don dep va thoat sach\n");
    return 0;
}

#include <signal.h>
#include <string.h>

static volatile sig_atomic_t nen_thoat = 0;
static void xu_ly(int s) { (void)s; nen_thoat = 1; }

int main(void) {
    struct sigaction sa;
    memset(&sa, 0, sizeof sa);
    sa.sa_handler = xu_ly;
    sigemptyset(&sa.sa_mask);       /* khong chan tin hieu nao khac trong handler */
    sa.sa_flags = SA_RESTART;       /* tu khoi dong lai syscall bi ngat */

    if (sigaction(SIGINT,  &sa, NULL) < 0) { perror("sigaction"); return 1; }
    if (sigaction(SIGTERM, &sa, NULL) < 0) { perror("sigaction"); return 1; }

    while (!nen_thoat) { lam_viec(); }
    don_dep();
    return 0;
}