std::generic_category (3) - Linux Manuals

std::generic_category: std::generic_category


std::generic_category - std::generic_category


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.



Return value

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


// 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';


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

See also

system_category identifies the operating system error category

errc the std::error_condition enumeration listing all standard <cerrno> macro constants