std::ios_base::Init
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                    | 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> declares (directly or indirectly) an instance of std::ios_base::Init with static storage duration, whose definition is provided by the C++ library: this makes it safe to access the standard I/O streams in the constructors and destructors of static objects (as long as #include <iostream> is present in the translation unit)
[edit] Member functions
| (constructor) | if *this is the first instance created, initializes the default C++ streams (public member function) | 
| (destructor) | if *this is the last instance created, flushes the default C++ streams (public member function) | 
[edit] See also
| reads from the standard C input stream stdin (global object) | |
| writes to the standard C output stream stdout (global object) | |
| writes to the standard C error stream stderr, unbuffered (global object) | |
| writes to the standard C error stream stderr (global object) |