std::streamsize

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C++ Standard Library
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Input/output library
I/O manipulators C-style I/O Buffers basic_streambuf basic_filebuf basic_stringbuf strstreambuf (deprecated) Streams Abstractions ios_base basic_ios basic_istream basic_ostream basic_iostream File I/O basic_ifstream basic_ofstream basic_fstream String I/O basic_istringstream basic_ostringstream basic_stringstream Array I/O istrstream (deprecated) ostrstream (deprecated) strstream (deprecated) Types streamoff streamsize fpos Error category interface iostream_category (C++11) io_errc (C++11)

Defined in header <ios>
typedef /*unspecified*/ streamsize;

The type std::streamsize is a signed integral type used to represent the number of characters transferred in an I/O operation or the size of an I/O buffer. It is used as a signed counterpart of std::size_t, similar to the POSIX type ssize_t.

Except in the constructors of std::strstreambuf, negative values of std::streamsize are never used.

[edit] See also

gcount	returns number of characters extracted by last unformatted input operation (public member function of std::basic_istream)
ignore	extracts and discards characters until the given character is found (public member function of std::basic_istream)
read	extracts blocks of characters (public member function of std::basic_istream)
write	inserts blocks of characters (public member function of std::basic_ostream)