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>

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

std::error_code represents a platform-dependent error code value. Eachstd::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 typestd::error_category, which corresponds to the said interface. The error code values are not required to be unique across different error categories.

[edit]Member functions

(constructor)	constructs an error code (public member function)[edit]
operator=	assigns another error code (public member function)[edit]
assign	assigns another error code (public member function)[edit]
Modifiers
clear	sets the`error_code` to value0 in`system_category` (public member function)[edit]
Observers
value	obtains the value of the`error_code` (public member function)[edit]
category	obtains the error_category for this error_code (public member function)[edit]
default_error_condition	obtains the`error_condition` for this`error_code` (public member function)[edit]
message	obtains the explanatory string for this`error_code` (public member function)[edit]
operator bool	checks if the value is non-zero (public member function)[edit]

[edit]Non-member functions

operator==operator!=operator<operator<=> (removed in C++20)(removed in C++20)(C++20)	compares two`error_code`s (function)[edit]
operator<<	outputs the value and the category name to an output stream (function)[edit]

[edit]Helper classes

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

[edit]See also

error_condition (C++11)	holds a portable error code (class)[edit]
error_category (C++11)	base class for error categories (class)[edit]
make_error_code(std::errc) (C++11)	creates error code value for`errc` enume (function)[edit]