/*************************************************************************
> File Name: main.c
> Author: 杨永利
> Mail: 1795018360@qq.com
> Created Time: 2021年07月16日 星期五 17时42分46秒
************************************************************************/#include<unistd.h>#include<stdio.h>#include<stdlib.h>intmain(int argc,charconst*argv[]){pid_t pid;
pid =fork();if(pid <0){// fork 出错,创建子进程失败perror("fork error:");exit(1);}elseif(pid ==0){// 子进程printf("I am the child process.\n");//输出进程 ID 和父进程 IDprintf("pid: %d\tppid:%d\n",getpid(),getppid());printf("I will sleep five seconds.\n");//睡眠 5s,保证父进程先退出sleep(5);printf("pid: %d\tppid:%d\n",getpid(),getppid());printf("child process is exited.\n");}else{// 父进程printf("I am father process.\n");//父进程睡眠 1s,保证子进程输出进程 idsleep(1);printf("father process is exited.\n");}return0;}