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std::basic_...buf::setbuf(3)   C++ Standard Libary  std::basic_...buf::setbuf(3)

NAME
     std::basic_stringbuf::setbuf - std::basic_stringbuf::setbuf

Synopsis
	protected:
	virtual   std::basic_streambuf<CharT,  Traits>*  setbuf(  char_type*  s,
     std::streamsize
	n )

	If s is a null pointer and n is zero, this function has no effect.

	Otherwise, the effect is implementation-defined: some implementations do
     nothing,
	while some implementations clear the std::string member  currently  used
     as the buffer
	and begin using the user-supplied character array of size n, whose first
     element is
	pointed to by s, as the buffer and the input/output character sequence.

	This  function	is protected virtual, it may only be called through pub-
     setbuf() or
	from member functions of a  user-defined  class  derived  from	std::ba-
     sic_stringbuf.

Parameters
	s - pointer to the first CharT in the user-provided buffer or null
	n - the number of CharT elements in the user-provided buffer or zero

Return value
	this

Notes
	The  deprecated  stream  buffer std::strstreambuf or the boost.IOStreams
     device
	boost::basic_array may be used to implement I/O buffering over	a  user-
     provided char
	array in portable manner.

Example
	Test for the stringstream's setbuf functionality.

     // Run this code

      #include <iostream>
      #include <sstream>

      int main()
      {
	  std::ostringstream ss;
	  char c[1024] = {};
	  ss.rdbuf()->pubsetbuf(c, 1024);
	  ss << 3.14 << '\n';
	  std::cout << c << '\n';
      }

Output:
      3.14 (on GNU g++/libstdc++ and SunPro C++/roguewave)
      <nothing> (on MS Visual Studio 2010, SunPro C++/stlport4, CLang++/libc++)

See also
	pubsetbuf invokes setbuf()
		  (public member function of std::basic_streambuf<CharT,Traits>)

http://cppreference.com 	   2024.06.10	    std::basic_...buf::setbuf(3)
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