System clock.
System clock represents the system-wide real time wall clock.
It may not be monotonic: on most systems, the system time can be adjusted at any moment. It is the only clock that has the ability to be displayed and converted to/from UNIX timestamp.
To get the current time:
static time_point now() noexcept
To convert a time_point to/from UNIX timestamp:
::boost::chrono::time_point< system_clock > time_point
constexpr system_clock::time_point fromUnixTimestamp(system_clock::duration d)
Convert UNIX timestamp to system_clock::time_point.
constexpr Duration toUnixTimestamp(const system_clock::time_point &tp)
Convert system_clock::time_point to UNIX timestamp.
::boost::chrono::milliseconds milliseconds
Definition at line 199 of file time.hpp.