timers.c   [plain text]

/*
 * Copyright (c) 2008 Apple Inc.  All rights reserved.
 *
 * @APPLE_DTS_LICENSE_HEADER_START@
 * 
 * IMPORTANT:  This Apple software is supplied to you by Apple Computer, Inc.
 * ("Apple") in consideration of your agreement to the following terms, and your
 * use, installation, modification or redistribution of this Apple software
 * constitutes acceptance of these terms.  If you do not agree with these terms,
 * please do not use, install, modify or redistribute this Apple software.
 * 
 * In consideration of your agreement to abide by the following terms, and
 * subject to these terms, Apple grants you a personal, non-exclusive license,
 * under Apple's copyrights in this original Apple software (the "Apple Software"),
 * to use, reproduce, modify and redistribute the Apple Software, with or without
 * modifications, in source and/or binary forms; provided that if you redistribute
 * the Apple Software in its entirety and without modifications, you must retain
 * this notice and the following text and disclaimers in all such redistributions
 * of the Apple Software.  Neither the name, trademarks, service marks or logos of
 * Apple Computer, Inc. may be used to endorse or promote products derived from
 * the Apple Software without specific prior written permission from Apple.  Except
 * as expressly stated in this notice, no other rights or licenses, express or
 * implied, are granted by Apple herein, including but not limited to any patent
 * rights that may be infringed by your derivative works or by other works in
 * which the Apple Software may be incorporated.
 * 
 * The Apple Software is provided by Apple on an "AS IS" basis.  APPLE MAKES NO
 * WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION THE IMPLIED
 * WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE, REGARDING THE APPLE SOFTWARE OR ITS USE AND OPERATION ALONE OR IN
 * COMBINATION WITH YOUR PRODUCTS. 
 * 
 * IN NO EVENT SHALL APPLE BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * ARISING IN ANY WAY OUT OF THE USE, REPRODUCTION, MODIFICATION AND/OR
 * DISTRIBUTION OF THE APPLE SOFTWARE, HOWEVER CAUSED AND WHETHER UNDER THEORY OF
 * CONTRACT, TORT (INCLUDING NEGLIGENCE), STRICT LIABILITY OR OTHERWISE, EVEN IF
 * APPLE HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * 
 * @APPLE_DTS_LICENSE_HEADER_END@
 */

#include <assert.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <sys/errno.h>
#include <mach/clock_types.h>

#include <dispatch/dispatch.h>

int main(int argc, char* argv[])
{
	dispatch_source_t theTimer = dispatch_source_create(DISPATCH_SOURCE_TYPE_TIMER, 0, 0, dispatch_queue_create("timer queue",NULL));

	__block int i = 0;

	printf("Starting to count by seconds\n");
	
	dispatch_source_set_event_handler(theTimer, ^{
			printf("%d\n", ++i);
			if (i >= 6) {
				printf("i>6\n");
				dispatch_source_cancel(theTimer);
			}
			if (i == 3) {
				printf("switching to half seconds\n");
				dispatch_source_set_timer(theTimer, DISPATCH_TIME_NOW, NSEC_PER_SEC / 2, 0);
			}
	});
	
	dispatch_source_set_cancel_handler(theTimer, ^{
		printf("dispatch source canceled OK\n");
		dispatch_release(theTimer);
		exit(0);
	});
	
	dispatch_source_set_timer(theTimer, dispatch_time(DISPATCH_TIME_NOW,NSEC_PER_SEC) , NSEC_PER_SEC, 0);
	
	dispatch_resume(theTimer);
	dispatch_main();
	
	return 0;
}