system_clock Structure
Represents a clock type that is based on the real-time clock of the system.
struct system_clock;
Remarks
A clock type is used to obtain the current time. The type embodies an instantiation of duration and the class template time_point, and defines a static member function now() that returns the time.
A clock is monotonic if the value that is returned by a first call to now() is always less than or equal to the value that is returned by a subsequent call to now().
A clock is steady if it is monotonic and if the time between clock ticks is constant.
In this implementation, a system_clock is synonymous with a high_resolution_clock.
Members
Public Typedefs
Name |
Description |
---|---|
system_clock::duration |
A synonym for duration<rep, period>. |
system_clock::period |
A synonym for the type that is used to represent the tick period in the contained instantiation of duration. |
system_clock::rep |
A synonym for the type that is used to represent the number of clock ticks in the contained instantiation of duration. |
system_clock::time_point |
A synonym for time_point<Clock, duration>, where Clock is a synonym for either the clock type itself or another clock type that is based on the same epoch and has the same nested duration type. |
Public Methods
Name |
Description |
---|---|
Static. Returns a time_point that most closely approximates a specified time. |
|
Static. Returns the current time. |
|
Static. Returns a time_t object that most closely approximates a specified time_point. |
Public Constants
Name |
Description |
---|---|
Specifies whether the clock type is monotonic. |
|
Specifies whether the clock type is steady. |
Requirements
Header: chrono
Namespace: std::chrono