std::pmr::get_default_resource

 

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在标头 <memory_resource> 定义
std::pmr::memory_resource* get_default_resource() noexcept;		(C++17 起)

获取默认的 memory_resource 指针。

默认 memory_resource 指针为某些设施在未显式提供 memory_resource 使所用。初始的默认 memory_resource 指针是 std::pmr::new_delete_resource 的返回值。

此函数是线程安全的。先前对 std::pmr::set_default_resource 的调用同步于（见 std::memory_order ） 后继的 std::pmr::get_default_resource 调用。

返回值

返回默认 memory_resource 指针的值。

参阅

set_default_resource (C++17)	设置缺省 std::pmr::memory_resource (函数)
new_delete_resource (C++17)	返回一个静态的程序范围 std::pmr::memory_resource，它使用全局 operator new 与 operator delete 分配和解分配内存 (函数)