p6-12.c

UNIX程序设计教程

#include<stdio.h>
#include<stdlib.h>
#include <sys/wait.h>
#include <signal.h>
#include "err_exit.h"
void pr_exit(int);    /* 程序6-6 */
int main(void)
{
        int status;
        if((status = system("date"))<0)
                err_exit("system() error");
        pr_exit(status);
        if((status = system("nonsuchcommand"))<0)
                err_exit("system() error");
        pr_exit(status);
        if((status = system("who;exit 44"))<0)
                err_exit("system() error");
        pr_exit(status);
        exit(EXIT_SUCCESS);
}