std::basic_filebuf<CharT,Traits>::swap

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 objects, it is rarely necessary to call it directly.

Example

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

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

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