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 returnstd::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)