std::generic_category

 

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Error handling

Exception handling exception uncaught_exceptionuncaught_exceptions (until C++20)(C++17) exception_ptr (C++11) make_exception_ptr (C++11) current_exception (C++11) rethrow_exception (C++11) nested_exception (C++11) throw_with_nested (C++11) rethrow_if_nested (C++11) Exception handling failures terminate terminate_handler get_terminate (C++11) set_terminate bad_exception unexpected (until C++17) unexpected_handler (until C++17) get_unexpected (C++11)(until C++17) set_unexpected (until C++17) Contracts contract_violation (C++20)

Exception categories logic_error invalid_argument domain_error length_error out_of_range runtime_error range_error overflow_error underflow_error tx_exception (TM TS) Error codes Error codes errno Assertions assert system_error facility error_category (C++11) generic_category (C++11) system_category (C++11) error_condition (C++11) errc (C++11) error_code (C++11) system_error (C++11)

 

Defined in header <system_error>
const std::error_category& generic_category() noexcept;		(since C++11)

Obtains a reference to the static error category object for generic errors. The object is required to override the virtual function error_category::name() to return a pointer to the string "generic". It is used to identify error conditions that correspond to the POSIX errno codes.

Parameters

(none)

Return value

A reference to the static object of unspecified runtime type, derived from std::error_category.

Example

Run this code

#include <iostream>
#include <system_error>
#include <cerrno>
#include <string>
int main()
{
    std::error_condition econd = std::generic_category().default_error_condition(EDOM);
    std::cout << "Category: " << econd.category().name() << '\n'
              << "Value: " << econd.value() << '\n'
              << "Message: " << econd.message() << '\n';
}

Output:

Category: generic
Value: 33
Message: Numerical argument out of domain

See also

system_category (C++11)	identifies the operating system error category (function)
errc (C++11)	the std::error_condition enumeration listing all standard <cerrno> macro constants (class)