#include<stdio.h>
#include<signal.h>
#include<unistd.h>
void sigAlrm(int signal)
{}

unsigned int mysleep(unsigned int second)
{
    struct sigaction sig,osig;
    sig.sa_handler = sigAlrm;
    sigemptyset(&sig.sa_mask);
    sig.sa_flags = 0;

    sigaction(SIGALRM,&sig,&osig);
    alarm(second);
    pause();
    unsigned int ret = alarm(0);
    sigaction(SIGALRM,&sig,NULL);
    return ret;
}

int main()
{
    while(1)
    {
        mysleep(2);
        printf("sleep 2 second\n");
    }
    return 0;
}