程式語言 - GNU - C/C++ - Daemon

參考資訊：
https://github.com/pasce/daemon-skeleton-linux-c

main.c

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

static void run_daemon(void)
{
    int x = 0;
    pid_t pid = 0;

    pid = fork();
    if (pid < 0) {
        exit(EXIT_FAILURE);
    }
    if (pid > 0) {
        exit(EXIT_SUCCESS);
    }
    if (setsid() < 0) {
        exit(EXIT_FAILURE);
    }

    signal(SIGCHLD, SIG_IGN);
    signal(SIGHUP, SIG_IGN);
    pid = fork();
    if (pid < 0) {
        exit(EXIT_FAILURE);
    }
    if (pid > 0) {
        exit(EXIT_SUCCESS);
    }

    umask(0);
    chdir("/");
    for (x = sysconf(_SC_OPEN_MAX); x >= 0; x--) {
        close (x);
    }

    system("echo 123 > /tmp/daemon_start");
    sleep(3);
    system("echo 123 > /tmp/daemon_stop");
}

int main(int argc, char **argv)
{
    run_daemon();
    return 0;
}

執行

$ gcc main.c -o main
$ ./main
$ ls /tmp/daemon*
    /tmp/daemon_start
    /tmp/daemon_stop