sleep func

#include<stdio.h>#include<stdlib.h>#include<signal.h>void handler(int num){        if(num == SIGQUIT)        {                printf("receive sig num is %d\n",num);        }}int main(){        int n = 10;        signal(SIGQUIT,handler);        #if 0        while(n > 0)        {                n =sleep(n);        }        #else        sleep(n);//sleep is a interrutp sleep,if you want to not distrupt by interruop ,you shuould up        #endif}