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 represents a platform-dependent error code value. Each std::error_code object holds an error code value 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 are not required to 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)	creates error code value for errc enum e (function)