/* sleep1.c
 *	purpose	show how sleep works
 *	usage	sleep1
 *	outline	sets handler, sets alarm, pauses, then returns
 */

#include	<stdio.h>
#include	<signal.h>

// #define	SHHHH

main()
{
	void	nothing();

	printf("about to sleep for 4 seconds\n");
	signal(SIGALRM, SIG_IGN);		/* catch it	*/
	alarm(4);				/* set clock	*/
	pause();				/* freeze here	*/
	printf("Morning so soon?\n");		/* back to work	*/
}

void
nothing()
{
#ifndef SHHHH
	printf("Alarm received from kernel\n");
#endif
}