std::error_code

 

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std::error_code

Member functions

error_code::error_code

error_code::operator=

error_code::assign

Modifiers

error_code::clear

Observers

error_code::value

error_code::category

error_code::default_error_condition

error_code::message

error_code::operator bool

Non-member functions

operator==operator!=operator<operator<=> (until C++20)(until C++20)(C++20)

operator<<

Helper classes

is_error_code_enum

hash<std::error_code>

 

Defined in header <system_error>
class error_code;		(since C++11)

std::error_code is a platform-dependent error code. Each std::error_code object holds an error code originating from the operating system or some low-level interface and a pointer to an object of type std::error_category, which corresponds to the said interface. The error code values may be not unique across different error categories.

Member functions

(constructor)	constructs an error code (public member function)
operator=	assigns another error code (public member function)
assign	assigns another error code (public member function)
Modifiers
clear	sets the error_code to value 0 in system_category (public member function)
Observers
value	obtains the value of the error_code (public member function)
category	obtains the error_category for this error_code (public member function)
default_error_condition	obtains the error_condition for this error_code (public member function)
message	obtains the explanatory string for this error_code (public member function)
operator bool	checks if the value is non-zero (public member function)

Non-member functions

operator==operator!=operator<operator<=> (removed in C++20)(removed in C++20)(C++20)	compares two error_codes (function)
operator<<	outputs the value and the category name to an output stream (function)

Helper classes

is_error_code_enum (C++11)	identifies a class as an error_code enumeration (class template)
std::hash<std::error_code> (C++11)	hash support for std::error_code (class template specialization)

See also

error_condition (C++11)	holds a portable error code (class)
error_category (C++11)	base class for error categories (class)
make_error_code(std::errc) (C++11)	constructs an std::errc error code (function)