mutex_ceiling.c

来自「linux下多线程程序设计,包括signals,mutex,simple_onc」· C语言 代码 · 共 52 行

/********************************************************
 * An example source module to accompany...
 *
 * "Using POSIX Threads: Programming with Pthreads"
 *     by Brad nichols, Dick Buttlar, Jackie Farrell
 *     O'Reilly & Associates, Inc.
 *
 ********************************************************
 * mutex_ceiling.c
 */

#include <pthread.h>
#include <sched.h>
#include <unistd.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>

/*
#ifndef _POSIX_THREAD_PRIO_PROTECT
#error "This system does not support priority ceiling protection in mutex"
#endif
*/

pthread_mutex_t      m1;
pthread_mutexattr_t  mutexattr_prioceiling;

extern int	main(void)
{
	int rtn;
	int mutex_protocol, high_prio;
	
	/* What is the default protocol on the host? */
	
	if ((rtn = pthread_mutexattr_init(&mutexattr_prioceiling)) != 0)
		fprintf(stderr,"pthread_mutexattr_init: %s",strerror(rtn)),exit(1);
	
	/* Initialize a mutex with the attribute object */
	if ((rtn = pthread_mutex_init(&m1, &mutexattr_prioceiling)) != 0)
		fprintf(stderr,"pthread_mutexattr_init: %s",strerror(rtn)), exit(1);
	
	if ((rtn = pthread_mutex_lock(&m1)) != 0)
		fprintf(stderr,"pthread_mutex_lock: %s",strerror(rtn)), exit(1);
	
	if ((rtn = pthread_mutex_unlock(&m1)) != 0)
		fprintf(stderr,"pthread_mutex_unlock: %s",strerror(rtn)), exit(1);
	
	return 0;
}