创建两个子进程，在进程执行中让父进程捕获键盘上传来的中断信号。 当多捕捉到中断信号后，父进程向两个子进程发出信号，子进程捕捉到该信号后分别输出： （1）“child process1 is killed by parent！” （2）“child process2 is killed by parent！” -Create two sub-processes, in the process of implementation so that the parent proce