std::ios_base::Init

std::ios_base::Init

class Init;

This class is used to ensure that the default C++ streams (std::cin, std::cout, etc.) are properly initialized and destructed. The class tracks how many instances of it are created and initializes the C++ streams when the first instance is constructed as well as flushes the output streams when the last instance is destructed.

The header <iostream> behaves as if it defines (directly or indirectly) an instance of std::ios_base::Init with static storage duration: this makes it safe to access the standard I/O streams in the construct