#include <sys/time.h>
#include <sys/types.h>
#include <unistd.h>

int main(){

	int retval=1;
	struct timeval tv;
	tv.tv_sec = 5;
	tv.tv_usec = 0;
	fd_set rfds;
	FD_ZERO(&rfds);
	FD_SET(1,&rfds);
	if ( (retval = select(2, &rfds, NULL, NULL, &tv)) != 0) {
		printf("data is available now");
		exit(0);
	} else {
		exit(0);
	}
}