系统编程之进程管理 pipe

来源：互联网发布：linux误删文件恢复编辑：程序博客网时间：2024/05/01 23:23

#include<unistd.h>

#include <sys/types.h>

#include <sys/wait.h>

#include <errno.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

int main()

    int pipe_fd[2];

    pid_t pid;

    char buf_r[100];

   // char * p_wbuf;

    int r_num;

    memset(buf_r,0,sizeof(buf_r));

    /*创建管道*/

    if(pipe(pipe_fd)<0)

        printf("pipe create error\n");

        return -1;

    /*创建子进程*/

    if((pid=fork())==0) //child

        printf("\n");

        close(pipe_fd[1]);//关闭写端

        sleep(2);//让父进程先运行，这样父进程先写子进程后读

        if((r_num=read(pipe_fd[0],buf_r,10)) > 0)

            printf("%d numbers read from the pipe is %s\n",r_num,buf_r);

            exit(0);

    else if(pid >0) //parent

        close(pipe_fd[0]);//关闭读端

        if(write(pipe_fd[1],"Hello",5)!=-1)

            printf("parent write 1 hello\n");

        if(write(pipe_fd[1],"Pipe",4)!=-1)

            printf("parent write 2 Pipe \n");

        close(pipe_fd[1]);

        waitpid(pid,NULL,0);//等待子进程结束

        exit(0);

    return 0;

/*改变 10 5 4 三个数字*/