31 Input/output library [input.output]

31.6 Stream buffers [stream.buffers]

31.6.1 Header <streambuf> synopsis [streambuf.syn]

namespace std { template<class charT, class traits = char_traits<charT>> class basic_streambuf; using streambuf = basic_streambuf<char>; using wstreambuf = basic_streambuf<wchar_t>; }
The header <streambuf> defines types that control input from and output to character sequences.