多線程編程之：Linux線程編程

（3）使用實(shí)例。

下面的實(shí)例是在我們已經(jīng)很熟悉的實(shí)例的基礎(chǔ)上增加線程屬性設(shè)置的功能。為了避免不必要的復(fù)雜性，這里就創(chuàng)建一個(gè)線程，這個(gè)線程具有綁定和分離屬性，而且主線程通過(guò)一個(gè)finish_flag標(biāo)志變量來(lái)獲得線程結(jié)束的消息，而并不調(diào)用pthread_join()函數(shù)。

/*thread_attr.c*/

#include stdio.h>

#include stdlib.h>

#include pthread.h>

#define REPEAT_NUMBER 3 /* 線程中的小任務(wù)數(shù) */

#define DELAY_TIME_LEVELS 10.0 /* 小任務(wù)之間的最大時(shí)間間隔 */

int finish_flag = 0;

void *thrd_func(void *arg)

{

int delay_time = 0;

int count = 0;

printf(Thread is startingn);

for (count = 0; count  REPEAT_NUMBER; count++)

{

delay_time = (int)(rand() * DELAY_TIME_LEVELS/(RAND_MAX)) + 1;

sleep(delay_time);

printf(tThread : job %d delay = %dn, count, delay_time);

}

printf(Thread finishedn);

finish_flag = 1;

pthread_exit(NULL);

}

int main(void)

{

pthread_t thread;

pthread_attr_t attr;

int no = 0, res;

void * thrd_ret;

srand(time(NULL));

/* 初始化線程屬性對(duì)象 */

res = pthread_attr_init(attr);

if (res != 0)

{

printf(Create attribute failedn);

exit(res);

}

/* 設(shè)置線程綁定屬性 */

res = pthread_attr_setscope(attr, PTHREAD_SCOPE_SYSTEM);

/* 設(shè)置線程分離屬性 */

res += pthread_attr_setdetachstate(attr, PTHREAD_CREATE_DETACHED);

if (res != 0)

{

printf(Setting attribute failedn);

exit(res);

}

res = pthread_create(thread, attr, thrd_func, NULL);

if (res != 0)

{

printf(Create thread failedn);

exit(res);

}

/* 釋放線程屬性對(duì)象 */

pthread_attr_destroy(attr);

printf(Create tread successn);

while(!finish_flag)

{

printf(Waiting for thread to finish...n);

sleep(2);

}

return 0;

}