#include <unistd.h>

#include <sys/types.h>

#include <stdlib.h>

#include <signal.h>

#include <stdio.h>

//子进程个数

#define SUB_PRO_COUNT 10

//处理子进程的退出信号

void sub_quit_signal_handle(int sig);

//父进程的事件循环

void ParentCycle();

//子进程的事件循环

void ChildCycle();

int main(void)

{

    pid_t  pid;

    int i;

    //创建SUB_PRO_COUNT个子进程

    for(i=; i<SUB_PRO_COUNT; i++)

    {

        pid = fork();

        if(  == pid || - == pid )

            break;

    }

    //创建子进程失败

    if( - == pid )

    {

        printf("No. %d: fork error\n", i);

    }

    //子进程的事件循环

    else if(  == pid )

    {

        ChildCycle();

    }

    //父进程的事件循环

    else

    {

        ParentCycle();

    }

    return ;

}

void sub_quit_signal_handle(int sig)

{

    int status;

    //获取退出的那个子进程的状态

    int quit_pid = wait(&status);

    printf("sub process %d quit, exit status %d\n", quit_pid, status);

    //新创建一个子进程

    pid_t pid = fork();

    if(  == pid )

         ChildCycle();

}

void ParentCycle()

{

    printf("Parent process %d\n", getpid());

    signal(SIGCHLD, sub_quit_signal_handle);

    while()

        pause();

}

void ChildCycle()

{

    printf("create sub process id: %d, parent id: %d\n", getpid(), getppid());

    while()

        pause();

}