std::iostream_category - cppreference.com (original) (raw)

Obtains a reference to the static error category object for iostream errors. The object is required to override the virtual function error_category::name() to return a pointer to the string "iostream". It is used to identify error codes provided in the exceptions of type std::ios_base::failure.

[edit] Parameters

(none)

[edit] Return value

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

[edit] Example

#include #include   int main() { std::ifstream f("doesn't exist"); try { f.exceptions(f.failbit); } catch (const std::ios_base::failure& e) { std::cout << "Caught an ios_base::failure.\n" << "Error code: " << e.code().value() << " (" << e.code().message() << ")\n" << "Error category: " << e.code().category().name() << '\n';   } }

Possible output:

Caught an ios_base::failure. Error code: 1 (unspecified iostream_category error) Error category: iostream

[edit] Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

[edit] See also