pthread_cleanup_push和pthread_cleanup_pop清除函数是否执行的说明

示例1：

 #include <stdio.h>
 #include <pthread.h>

 void* clean(void* arg)
 {
     printf("cleanup:%s\n", (char*)arg);
     return (void*);
 }

 void* thrd_fn1(void* arg)
 {
     printf("thrd_fn1 start...\n");
     pthread_cleanup_push((void*)clean, "thread1 first handler");
     pthread_cleanup_push((void*)clean, "thread1 second handle");
     printf("thread1 push complete\n");
     if (arg)
     {
         return ((void*));
     }

     pthread_cleanup_pop(1);//当push和pop之间的代码有return时，即使pop的参数为1,也不执行push中的清除函数
     pthread_cleanup_pop();
     return (void*);
 }

 void* thrd_fn2(void* arg)
 {
     printf("thrd_fn2 start...\n");
     pthread_cleanup_push((void*)clean, "thread2 first handler");
     pthread_cleanup_push((void*)clean, "thread2 second handle");
     printf("thread2 push complete\n");
     if (arg)
     {
         pthread_exit((void*));
     }

     pthread_cleanup_pop();
     pthread_cleanup_pop();
     return (void*);
 }

 int main(int argc, char** argv)
 {
     int nRes = -;
     void* pRtVal = ;
     pthread_t ptid1,ptid2;

     nRes = pthread_create(&ptid1, NULL, thrd_fn1, (void*));
     if (nRes != )
     {
         printf("pthread1 creare failed\n");
         return -;
     }

     nRes = pthread_create(&ptid2, NULL, thrd_fn2, (void*));
     if (nRes != )
     {
         printf("pthread2 create failed\n");
         return -;
     }

     nRes = pthread_join(ptid1, &pRtVal);
     if (nRes != )
     {
         printf("pthread_join 1 failed\n");
         return -;
     }
     printf("pthread1 exit, code is %d\n", (int)pRtVal);

     nRes = pthread_join(ptid2, &pRtVal);
     if (nRes != )
     {
         printf("pthread_join 1 failed\n");
         return -;
     }
     printf("pthread2 exit, code is %d\n", (int)pRtVal);

     printf("test over!!!\n");

     return ;
 }

结果：

thrd_fn2 start...
thread2 push complete
cleanup:thread2 second handler
cleanup:thread2 first handler
thrd_fn1 start...
thread1 push complete
pthread1 exit, code is
pthread2 exit, code is
test over!!!

示例2：

 #include <stdio.h>
 #include <pthread.h>

 void* clean(void* arg)
 {
     printf("cleanup:%s\n", (char*)arg);
     return (void*);
 }

 void* thrd_fn1(void* arg)
 {
     printf("thrd_fn1 start...\n");
     pthread_cleanup_push((void*)clean, "thread1 first handler
     pthread_cleanup_push((void*)clean, "thread1 second handle
     printf("thread1 push complete\n");

     pthread_cleanup_pop();
     pthread_cleanup_pop();
     return (void*);
 }

 void* thrd_fn2(void* arg)
 {
     printf("thrd_fn2 start...\n");
     pthread_cleanup_push((void*)clean, "thread2 first handler
     pthread_cleanup_push((void*)clean, "thread2 second handle
     printf("thread2 push complete\n");
     if (arg)
     {
         pthread_exit((void*));
     }

     pthread_cleanup_pop();
     pthread_cleanup_pop();
     return (void*);
 }

 int main(int argc, char** argv)
 {
     int nRes = -;
     void* pRtVal = ;
     pthread_t ptid1,ptid2;

     nRes = pthread_create(&ptid1, NULL, thrd_fn1, (void*));
     if (nRes != )
     {
         printf("pthread1 creare failed\n");
         return -;
     }

     nRes = pthread_create(&ptid2, NULL, thrd_fn2, (void*));
     if (nRes != )
     {
         printf("pthread2 create failed\n");
         return -;
     }

     nRes = pthread_join(ptid1, &pRtVal);
     if (nRes != )
     {
         printf("pthread_join 1 failed\n");
         return -;
     }
     printf("pthread1 exit, code is %d\n", (int)pRtVal);

     nRes = pthread_join(ptid2, &pRtVal);
     if (nRes != )
     {
         printf("pthread_join 1 failed\n");
         return -;
     }
     printf("pthread2 exit, code is %d\n", (int)pRtVal);

     printf("test over!!!\n");

     return ;
 }

执行结果：

thrd_fn2 start...
thread2 push complete
cleanup:thread2 second handler
cleanup:thread2 first handler
thrd_fn1 start...
thread1 push complete
cleanup:thread1 second handler
cleanup:thread1 first handler
pthread1 exit, code is
pthread2 exit, code is
test over!!!