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In the C++ programming language, Input/output library refers to a family of class templates and supporting functions in the C++ Standard Library that implement stream-based input/output capabilities.〔''ISO/IEC 14882:2003 Programming Languages — C++. ()/1''〕 It is an object-oriented alternative to C's FILE-based streams from the C standard library. ==Overview== Most of the classes in the library are actually very generalized class templates. Each template can operate on various character types, and even the operations themselves, such as how two characters are compared for equality, can be customized. However, the majority of code needs to do input and output operations using only one or two character types, thus most of the time the functionality is accessed through several typedefs, which specify names for commonly used combinations of template and character type. For example, basic_fstream refers to the generic class template that implements input/output operations on file streams. It is usually used as fstream which is an alias for basic_fstream, or, in other words, basic_fstream working on characters of type char with the default character operation set.The classes in the library could be divided into roughly two categories: abstractions and implementations. Classes, that fall into abstractions category, provide an interface which is sufficient for working with any type of a stream. The code using such classes doesn't depend on the exact location the data is read from or is written to. For example, such code could write data to a file, a memory buffer or a web socket without a recompilation. The implementation classes inherit the abstraction classes and provide an implementation for concrete type of data source or sink. The library provides implementations only for file-based streams and memory buffer-based streams. The classes in the library could also be divided into two groups by whether it implements low-level or high-level operations. The classes that deal with low-level stuff are called stream buffers. They operate on characters without providing any formatting functionality. These classes are very rarely used directly. The high-level classes are called streams and provide various formatting capabilities. They are built on top of stream buffers. The following table lists and categorizes all classes provided by the input-output library. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Input/output (C++)」の詳細全文を読む スポンサード リンク
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