阻塞型通信程序

 

#include"stdio.h"
#include"unistd.h"
#include"sys/types.h"
#include"signal.h"
#include"wait.h"

void sigchld_handler(int sig)
{
    pid_t pid;
    int status;
    for(;(pid=waitpid(-1,&status,WNOHANG))>0;)
    {
        printf("child %d died :%d\n",pid,WEXITSTATUS(status));
        printf("hi,parent process received SIHHLD signal successfully!\n");
    }
    return;
}

void main()
{
    //pid_t pc,pr;
    int pc=fork();
    if(pc==0)
    {
        printf("子进程！\n");
        sleep(1);
        printf("This is child process with pid of %d\n", getpid());
        //exit(1);
    }
    else if(pc>0)
    {
        signal(SIGCHLD,sigchld_handler);
        pause();
    }
    else
    {
        printf("创建进程出错！\n");
        exit(1);
    }
}