![]() ![]() basic_iostream template and iostream class is declared in the header, not header. Take note that istream and ostream are unidirectional streams whereas iostream is bidirectional. iostream ( basic_iostream): subclass of both istream and ostream, which supports bidirectional input and output operations. ![]() istream ( basic_istream), ostream ( basic_ostream): provide the input and output public interfaces.The superclass ios_base (which is not a template class) maintains data that is independent of the template parameters whereas the subclass ios (instantiation of template basic_ios) maintains data which is dependent of the template parameters. ios_base and ios: superclasses to maintain common stream properties such as format flag, field width, precision and locale.We shall focus on the specialization classes for char type: C++ further provides typedef statements to name these classes: traits, of another template class char_traits, defined the properties of the character operations such as the collating sequence (sorting order) of character set.Īs mention, the basic_xxx template classes can be instantiated with a character type, such as char and wchar_t.charT is the character type, such as char or wchar_t.Most of the template classes take two type parameters. In order to support various character sets ( char and wchar_t in C++98/03 and char16_t, char32_t introduced in C++11), the stream classes are written as template classes, which could be instantiated with an actual character type. Furthermore, the header provided manipulators such as setw(), setprecision() setfill() and setbase() for formatting. Disconnect (Dissociate) the stream to the actual IO device (e.g., close the file).Ĭ++ IO Headers, Templates and Classes HeadersĬ++ IO is provided in headers (which included, , and ), (for file IO), and (for string IO).Some functions convert the data between the external format and internal format (formatted IO) while other does not (unformatted or binary IO). Perform input/output operations on the stream, via the functions defined in the stream's pubic interface in a device independent manner.Connect (Associate) the stream object to an actual IO device (e.g., keyboard, console, file, network, another program).To perform input and output, a C++ program: ![]() Formatted IO operations are supported via overloading the stream insertion ( >) operators, which presents a consistent public IO interface. In unformatted or low-level IO, bytes are treated as raw bytes and unconverted. In formatted or high-level IO, bytes are grouped and converted to types such as int, double, string or user-defined types. Streams acts as an intermediaries between the programs and the actual IO devices, in such the way that frees the programmers from handling the actual devices, so as to archive device independent IO operations.Ĭ++ provides both the formatted and unformatted IO functions. In output operations, data bytes flow from the program to an output sink (such as console, file, network or another program). In input operations, data bytes flow from an input source (such as keyboard, file, network or another program) into the program. The same set of operations can be applied to different types of IO devices.Ĭ/C++ IO are based on streams, which are sequence of bytes flowing in and out of the programs (just like water and oil flowing through a pipe).
0 Comments
Leave a Reply. |