pthread_cleanup_push_defer_np函数用法详解

pthread_cleanup_push_defer_np函数简介

• 头文件包含

#include <pthread.h>

• 函数定义

void pthread_cleanup_push_defer_np(void (* routine )(void *),
                                   void * arg );
void pthread_cleanup_pop_restore_np(int  execute );

• 编译链接选项

-pthread

pthread_cleanup_push_defer_np函数常见使用错误

• 链接错误
  undefined reference to `pthread_cleanup_push_defer_np'
  解决办法：添加链接选项

-pthread

• 编译错误
  warning: implicit declaration of function ‘pthread_cleanup_push_defer_np’ [-Wimplicit-function-declaration]
  解决办法：包含头文件

#include <pthread.h>

pthread_cleanup_push_defer_np函数详细描述

这些函数与pthread_cleanup_push (3)和pthread_cleanup_pop (3)相同，只是在本页中注意到了不同之处。
与pthread_cleanup_push (3)一样，pthread_cleanup_push_defer_np ()将routine推送到线程的取消清理处理程序堆栈上。此外，它还保存线程当前的可取消性类型，并将可取消性类型设置为“deferred”（请参见pthread_setcanceltype (3));。这确保即使线程的可取消性类型在调用之前是“异步的”，也会发生取消清理。
与pthread_cleanup_pop (3)类似，pthread_cleanup_pop_restore_np ()从线程的取消清理处理程序堆栈中弹出最上面的清理处理程序。此外，它将线程的可取消性类型还原为匹配pthread_cleanup_push_defer_np ()时的值
调用方必须确保对这些函数的调用在同一函数中成对，并且处于同一词法嵌套级别。适用其他限制，如pthread_cleanup_push (3)中所述
以下调用序列：

pthread_cleanup_push_defer_np(routine, arg);
pthread_cleanup_pop_restore_np(execute);

相当于（但比）：

int oldtype;

pthread_cleanup_push(routine, arg);
pthread_setcanceltype(PTHREAD_CANCEL_DEFERRED, &oldtype);
\&...
pthread_setcanceltype(oldtype, NULL);
pthread_cleanup_pop(execute);