<system_error>

System errors

This header defines a series of standardized elements to report error conditions originating from the operating system or other low-level operations.

Most such errors are identified by a single integer value, which is sometimes system-specific. The class error_code encapsulates and preserves these system-generated values associating them with an error_category.

These objects can be compared against objects of type error_condition, which is a very similar type meant to represent the same errors, but in a portable way. In this way, library calls to the system may produce error_code values (which preserve system-specific values), and programs can compare them against error_condition objects (which are portable between systems).

error_category objects identify different sets of error codes and also determine the correspondences between error codes and error conditions.

This header defines two categories: generic_category and a system_category. Other libraries may define additional error categories (such as the standard iostream_category, defined in <ios>).

The class system_error is a standard exception type that carries an error_code object.

Classes

error_category: Error category (abstract class)

error_code: Error code (class)

error_condition: Error condition (class)

system_error: System error exception (class)

Trait classes:

is_error_code_enum: error_code enum flag (class)

is_error_condition_enum: error_condition enum flag (class)

Enum classes:

errc: Generic error conditions (enum class)

Functions

Constructor helpers:

make_error_code: Make error code (function)

make_error_condition: Make error condition (function)

classes

enum classes