std::basic_filebuf::swap
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                    < cpp | io | basic filebuf
                    
                                                            
                    |   void swap( std::basic_filebuf& rhs )  | 
(since C++11) | |
Swaps the state and the contents of *this and rhs.
Contents | 
[edit] Parameters
| rhs | - |   another basic_filebuf
 | 
[edit] Return value
(none)
[edit] Notes
This function is called automatically when swapping std::fstream objects, it is rarely necessary to call it directly.
[edit] 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 }
 
[edit] See also
|    (C++11)  | 
   assigns a basic_filebuf object   (public member function)  | 
|    specializes the std::swap algorithm  (function template)  | |
|    (C++11)  | 
   swaps two file streams   (public member function of std::basic_fstream) 
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