Section 3: library functions
std::error_condition::message – std::error_condition::message Synopsis std::string message() const; (since C++11) Returns an explanatory message for the stored error code and error category. Effectively calls category().message(value()). Parameters (none) Return value An explanatory message for the stored error code and error category. Exceptions (none)
std::error_condition::error_condition – std::error_condition::error_condition Synopsis error_condition() noexcept; (1)(since C++ 11) error_condition(const error_condition &other) noexcept; (2)(since C++ 11)(implicitly declared) error_condition(int val, const error_category &cat) noexcept; (3)(since C++ 11) template <class ErrorConditionEnum> (4)(since C++ 11) error_condition(ErrorConditionEnum e) noexcept; Constructs new error condition. 1) Default constructor. Initializes the error condition with generic category and error code 0. 2) Copy…
std::error_condition::clear – std::error_condition::clear Synopsis void clear() noexcept; (since C++ 11) Clears the state of the error condition. Sets the error code to 0 and error category to std::generic_category. Parameters (none) Return value (none)
std::error_condition::category – std::error_condition::category Synopsis const error_category &category() const noexcept; (since C++ 11) Returns the stored error category. Parameters (none) Return value The stored error category.
std::error_condition::assign – std::error_condition::assign Synopsis void assign(int val, const error_category &cat) noexcept; (since C++ 11) Assigns contents to an error condition. Sets the error code to val and error category to cat. Parameters val – error code cat – error category Return value (none)
std::error_condition – std::error_condition Synopsis Defined in header <system_error> class error_condition; (since C++11) std::error_condition is a platform-independent error code. Like std::error_code, it is uniquely identified by an integer value and a std::error_category, but unlike std::error_code, the value is not platform-dependent. A typical implementation holds one integer data member (the value) and a pointer to an std::error_category….
std::error_code::value – std::error_code::value Synopsis int value() const noexcept; (since C++ 11) Returns the platform dependent error value. Parameters (none) Return value The platform-dependent error value. See also obtains the error_category for this error_code category (public member function)
std::error_code::operatorbool – std::error_code::operatorbool Synopsis explicit operator bool() const noexcept; (since C++11) Checks if the error value is valid, i.e. non-zero. Parameters (none) Return value false if value() == 0, true otherwise.
std::error_code::operator= – std::error_code::operator= Synopsis template< class ErrorCodeEnum > (since C++11) error_code& operator=( ErrorCodeEnum e ) noexcept; Replaces the error code and corresponding category with those representing error code enum e. Equivalent to *this = std::make_error_code(e). The overload participates in overload resolutions only if std::is_error_code_enum<ErrorCodeEnum>::value == true. Parameters e – error code enum to construct Return…
std::error_code::message – std::error_code::message Synopsis std::string message() const; (since C++11) Returns the message corresponding to the current error value and category. Equivalent to category().message(value()). Parameters (none) Return value The error message corresponding to the current error value and category. Exceptions (none)
std::error_code::error_code – std::error_code::error_code Synopsis error_code() noexcept; (1)(since C++ 11) error_code(int ec, const error_category &ecat) noexcept; (2)(since C++ 11) template <class ErrorCodeEnum> (3)(since C++ 11) error_code(ErrorCodeEnum e) noexcept; Constructs new error code. 1) Constructs error code with default value. Equivalent to error_code(0, std::system_category()). 2) Constructs error code with ec as the platform-dependent error code and ecat…
std::error_code::default_error_condition – std::error_code::default_error_condition Synopsis std::error_condition default_error_condition() const noexcept; (since C++11) Returns the default error condition for the current error value. Equivalent to category().default_error_condition(value()). Parameters (none) Return value The default error condition for the current error value.
std::error_code::clear – std::error_code::clear Synopsis void clear() noexcept; (since C++ 11) Replaces the error code and error category with default values. Equivalent to *this = error_code(0, std::system_category()). Parameters (none) Return value (none)
std::error_code::category – std::error_code::category Synopsis const std::error_category &category() const noexcept; (since C++ 11) Returns the error category of the error value. Parameters (none) Return value The error category of the error value. See also obtains the value of the error_code value (public member function)
std::error_code::assign – std::error_code::assign Synopsis void assign(int ec, const error_category &ecat) noexcept; (since C++ 11) Replaces the contents with error code ec and corresponding category ecat. Parameters ec – platform-dependent error code enum to assign ecat – error category corresponding to ec Return value (none) See also assigns another error code operator= (public member function)
std::error_code – std::error_code Synopsis Defined in header <system_error> class error_code; (since C++11) std::error_code is a platform-dependent error code. Each std::error_code object holds an error code originating from the operating system or some low-level interface and a pointer to an object of type std::error_category, which corresponds to the said interface. The error code values may be…
std::error_category::operator==,!=,< – std::error_category::operator==,!=,< Synopsis bool operator==( const error_category& rhs ) const noexcept; (1) (since C++11) bool operator!=( const error_category& rhs ) const noexcept; (2) (since C++11) bool operator<( const error_category& rhs ) const noexcept; (3) (since C++11) Compares to another error category. 1) Checks whether *this and rhs refer to the same object. 2) Checks…
std::error_category::name – std::error_category::name Synopsis virtual const char *name() const noexcept = 0; (since C++ 11) Returns a pointer to a null-terminated byte string that specifies the name of the error category. Parameters (none) Return value Null-terminated byte string specifying the name of the error category.
std::error_category::message – std::error_category::message Synopsis virtual std::string message(int condition) const = 0; (since C++ 11) Returns a string describing the given error condition for the error category represented by *this. Parameters condition – specifies the error condition to describe Return value A string describing the given error condition. Exceptions (none)
std::error_category::~error_category – std::error_category::~error_category Synopsis virtual ~error_category(); (since C++11) Destroys the object. Parameters (none)