std:: error_category

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

std::error_category serves as the base class for specific error category types, such as std::system_category , std::iostream_category , etc. Each specific category class defines the error_code - error_condition mapping and holds the explanatory strings for all error_conditions. The objects of error category classes are treated as singletons, passed by reference.

Member functions

(constructor)	constructs an error_category (public member function)
(destructor) [virtual]	destructs an error_category (virtual public member function)
operator= [deleted]	not copy assignable (public member function)
name [virtual]	obtains the name of the category (virtual public member function)
default_error_condition [virtual]	maps error_code to error_condition (virtual public member function)
equivalent [virtual]	compares error_code and error_condition for equivalence (virtual public member function)
message [virtual]	obtains the explanatory string (virtual public member function)
operator== operator!= operator< operator<=> (removed in C++20) (removed in C++20) (C++20)	compares two error categories (function)

Specific error categories

generic_category (C++11)	identifies the generic error category (function)
system_category (C++11)	identifies the operating system error category (function)
iostream_category (C++11)	identifies the iostream error category (function)
future_category (C++11)	identifies the future error category (function)

See also

error_condition (C++11)	holds a portable error code (class)
error_code (C++11)	holds a platform-dependent error code (class)