std::make_error_code(std::io_errc)

 

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make_error_code(std::io_errc) (C++11)

make_error_condition(std::io_errc) (C++11)

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is_error_code_enum<std::io_errc> (C++11)

 

Defined in header <ios>
std::error_code make_error_code( std::io_errc e ) noexcept;		(since C++11)

Constructs an std::error_code object from a value of type std::io_errc as if by return std::error_code(static_cast<int>(e), std::iostream_category()).

This function is called by the constructor of std::error_code with an std::io_errc argument.

Parameters

e

-

error code number

Return value

A value of type std::error_code that holds the error code number from e associated with the error category "iostream".

Example

Run this code

#include <iostream>
#include <system_error>
 
int main()
{
    std::error_code ec = std::make_error_code(std::io_errc::stream);
 
    // This works because of the overloaded method
    //    and the is_error_code_enum specialization.
    ec = std::io_errc::stream;
 
    std::cout << "Error code from io_errc::stream has category "
              << ec.category().name() << '\n';
}

Output:

Error code from io_errc::stream has category iostream

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR	Applied to	Behavior as published	Correct behavior
LWG 2087	C++11	make_error_code(io_errc) was not declared noexcept	declared noexcept

See also

error_code (C++11)	holds a platform-dependent error code (class)
io_errc (C++11)	the IO stream error codes (enum)
make_error_code(std::errc) (C++11)	creates error code value for errc enum e (function)
make_error_code(std::future_errc) (C++11)	constructs a future error code (function)