Linux进程间软中断通信

#include<unistd.h>
#include<string.h>
#include<stdlib.h>
#include<stdio.h>
#include<signal.h>
#include<sys/types.h>
#include<sys/wait.h>
pid_t pid1,pid2;
void CallKill(int a)
{
        kill(pid1,20);
        kill(pid2,21);
}
void Child_1()
{
        printf("Child Process1 is Killed by Parent!\r\n");
        exit(0);
}
void Child_2()
{
        printf("Child Process2 is Killed by Parent!\r\n");
        exit(0);
}
int main()
{
       pid1 = fork();
       if(pid1 == 0)
       {
                //signal(SIGINT,SIG_IGN);//忽略收到的中断指令
                signal(SIGQUIT,SIG_IGN);
                signal(20,Child_1);//注册中断信号对应的函数指针
                sleep(5);//切换进程
       }
       else
       {
                pid2 = fork();
                if(pid2 == 0)
                {
                        //signal(SIGINT,SIG_IGN);
                        signal(SIGQUIT,SIG_IGN);
                        signal(21,Child_2);//注册中断信号对应的函数指针
                        sleep(5);
                }
                else
                {
                        //signal(SIGINT,CallKill);
                        signal(SIGQUIT,CallKill);
                        sleep(10);//切换到子进程去执行
                        wait(0);//等待子进程全部推出
                        wait(0);
                        printf("Parent Process is Killed\r\n");
                        exit(0);
                }
       }
       return 0;
}