std::pmr::get_default_resource

 

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定义在头文件 <memory_resource> 中
std::pmr::memory_resource* get_default_resource() noexcept;		(自 C++17 起)

获取默认内存资源指针。

当没有提供显式内存资源时，某些工具会使用默认内存资源指针。最初的默认内存资源指针是std::pmr::new_delete_resource的返回值。

此函数是线程安全的。对std::pmr::set_default_resource的先前调用与（见 std::memory_order）后续的 std::pmr::get_default_resource 调用同步。

返回值

返回默认内存资源指针的值。

另请参阅

set_default_resource (C++17)	设置默认的 std::pmr::memory_resource (函数)
new_delete_resource (C++17)	返回一个使用全局 operator new 和 operator delete 来分配和释放内存的静态的程序级 std::pmr::memory_resource (函数)