thread.c

嵌入式linux开发应用程序中 多个线程的实例

/*
****************************************Copyright (c)**************************************************
**                               Guangzhou Zhiyuan Electronic Co.,LTD.
**                                     graduate school
**                                 http://www.zyinside.com
**
**------------------------------------- File Info ------------------------------------------------------
** File name:           thread.c
** Last modified Date:  2005-12-30
** Last Version:        1.0
** Descriptions:        Demo multi-thread program.
**------------------------------------------------------------------------------------------------------
** Created by:          Chenxibing
** Created date:        2005-12-30
** Version:             1.0
** Descriptions:        Preliminary version.
**
**------------------------------------------------------------------------------------------------------
** Modified by:
** Modified date:
** Version:
** Descriptions:
**
********************************************************************************************************
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <pthread.h>

/*
*******************************************************************************************************
** Function name: main()
** Descriptions	: Demo for thread.
** Input	: NONE
** Output	: NONE
** Created by	: Chenxibing
** Created Date	: 2005-12-30
**-----------------------------------------------------------------------------------------------------
** Modified by	:
** Modified Date: 
**-----------------------------------------------------------------------------------------------------
*******************************************************************************************************
*/
int task1(int *cnt)
{
	while(*cnt < 5)
	{
		sleep(1);
		(*cnt)++;
		printf("task1 cnt = %d.\n", *cnt);
	}

	return (*cnt);
}

int task2(int *cnt)
{
	while(*cnt < 5)
	{
		sleep(2);
		(*cnt)++;
		printf("task2 cnt = %d.\n", *cnt);
	}

	return (*cnt);
}

int main(int argc, char **argv)
{
	int result;
	int t1 = 0;
	int t2 = 0;
	int rt1, rt2;
	pthread_t thread1, thread2;

	/* create the first thread. */
	result = pthread_create(&thread1, PTHREAD_CREATE_JOINABLE, (void *)task1, (void *)&t1);
	if(result)
	{
		perror("pthread_create: task1.\n");
		exit(EXIT_FAILURE);
	}

	/* create the second thread. */
	result = pthread_create(&thread2, PTHREAD_CREATE_JOINABLE, (void *)task2, (void *)&t2);
	if(result)
	{
		perror("pthread_create: task2.\n");
		exit(EXIT_FAILURE);
	}

	pthread_join(thread1, (void *)&rt1);
	pthread_join(thread2, (void *)&rt2);

	printf("total %d times.\n", t1+t2);
	printf("return value of task1: %d.\n", rt1);
	printf("return value of task2: %d.\n", rt2);

	exit(EXIT_SUCCESS);
}