std::swap(std::basic_ofstream)

 

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std::basic_ofstream

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basic_ofstream::basic_ofstream

basic_ofstream::operator= (C++11)

basic_ofstream::swap (C++11)

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Non-member functions

swap(std::basic_ofstream) (C++11)

 

template< class CharT, class Traits > void swap( basic_ofstream<CharT, Traits>& lhs, basic_ofstream<CharT, Traits>& rhs );

Specializes the std::swap algorithm for std::basic_ofstream. Exchanges the state of lhs with that of rhs. Effectively calls lhs.swap(rhs).

Parameters

lhs, rhs

-

streams whose state to swap

Return value

(none)

Exceptions

May throw implementation-defined exceptions.

Example

Run this code

#include <fstream>
#include <iostream>
#include <string>
 
bool create_stream(std::ofstream& fs)
{
    try
    {
        std::string some_name = "/tmp/test_file.txt";
        std::ios_base::openmode some_flags = fs.trunc; // | other flags
 
        if (std::ofstream ts{some_name, some_flags}; ts.is_open())
        {
            std::swap(ts, fs); // stream objects are not copyable => swap
            return true;
        }
    }
    catch (...)
    {
        std::cout << "Exception!\n";
    }
    return false;
}
 
int main()
{
    if (std::ofstream fs; create_stream(fs))
    {
        // use fs stream
    }
}

See also

swap (C++11)

swaps two file streams (public member function)