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std::basic_filebuf::swap(3)    C++ Standard Libary   std::basic_filebuf::swap(3)

NAME
     std::basic_filebuf::swap - std::basic_filebuf::swap

Synopsis
	void swap( std::basic_filebuf& rhs );  (since C++11)

	Swaps the state and the contents of *this and rhs.

Parameters
	rhs - another basic_filebuf

Return value
	(none)

Notes
	This  function	is  called  automatically when swapping std::fstream ob-
     jects, it is
	rarely necessary to call it directly.

Example
     // Run this code

      #include <fstream>
      #include <iostream>
      #include <string>

      int main()
      {
	  std::ifstream fin("test.in"); // read-only
	  std::ofstream fout("test.out"); // write-only

	  std::string s;
	  getline(fin, s);
	  std::cout << s << '\n'; // outputs the first line of test.in

	  fin.rdbuf()->swap(*fout.rdbuf()); //swap the underlying buffers

	  getline(fin, s); // fails: cannot read from a write-only filebuf
	  std::cout << s << '\n'; // prints empty line
      }

See also
	operator=		      assigns a basic_filebuf object
	(C++11) 		      (public member function)
	std::swap(std::basic_filebuf) specializes the std::swap algorithm
	(C++11) 		      (function template)
	swap			      swaps two file streams
	(C++11) 		      (public member function of
				      std::basic_fstream<CharT,Traits>)

http://cppreference.com 	   2024.06.10	     std::basic_filebuf::swap(3)
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