waitpidのサンプル

sample_waitpid.c

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

#include <sys/types.h>
#include <sys/wait.h>

int child()
{
    int count = 10;
    while (count--) {
        sleep(1);
        printf("c:hoge\n");
    }
    return 0;
}

int parent(int child_pid)
{
    int ret;
    int status;

    signal(SIGINT, SIG_IGN);
    signal(SIGHUP, SIG_IGN);
    signal(SIGTERM, SIG_IGN);
    do {
        ret = waitpid(child_pid, &status, 0);
        if (ret == -1) {
            perror("waitpid");
            exit(EXIT_FAILURE);
        }

        if (WIFEXITED(status)) {
                printf("exited, status=%d\n", WEXITSTATUS(status));
        }

        if (WIFSIGNALED(status)) {
                printf("killed by signal %d\n", WTERMSIG(status));
        }

        if (WIFSTOPPED(status)) {
                printf("stopped by signal %d\n", WSTOPSIG(status));
        } else if (WIFCONTINUED(status)) {
                printf("continued\n");
        }
        /*
        1       HUP (hang up)
        2       INT (interrupt)
        3       QUIT (quit)
        6       ABRT (abort)
        9       KILL (non-catchable, non-ignorable kill)
        14      ALRM (alarm clock)
        15      TERM (software termination signal)
        */
    } while (!WIFEXITED(status) && !WIFSIGNALED(status));

    printf("c:parent\n");
    return 0;
}


int main()
{
    int ret;
    ret = fork();
    if (ret == -1) {
        perror("fork");
        exit(EXIT_FAILURE);
    }

    if (ret == 0) {
        //child
        return child();
    } else {
        //parent
        return parent(ret);
    }
}