std::timespec_get

 

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Date and time library

Time point time_point (C++11) clock_time_conversion (C++20)   clock_cast (C++20) Duration duration (C++11) Clocks system_clock (C++11) steady_clock (C++11) is_clock (C++20) utc_clock (C++20) tai_clock (C++20) high_resolution_clock (C++11) gps_clock (C++20) file_clock (C++20) local_t (C++20) Time of day is_amis_pm (C++20)(C++20) make12make24 (C++20)(C++20) hh_mm_ss (C++20)

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time

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timespec_get (C++17)

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tm

time_t

clock_t

timespec (C++17)

 

Defined in header <ctime>
int timespec_get(std::timespec* ts, int base );	(1)	(since C++17)
#define TIME_UTC /* implementation-defined */	(2)	(since C++17)

1) Modifies the std::timespec object pointed to by ts to hold the current calendar time in the time base base.

2) Expands to a value suitable for use as the base argument of std::timespec_get.

Other macro constants beginning with TIME_ may be provided by the implementation to indicate additional time bases.

If base is TIME_UTC, then

• ts->tv_sec is set to the number of seconds since an implementation defined epoch, truncated to a whole value,
• ts->tv_nsec member is set to the integral number of nanoseconds, rounded to the resolution of the system clock.

Parameters

ts	-	pointer to an object of type std::timespec
base	-	TIME_UTC or another nonzero integer value indicating the time base

Return value

The value of base if successful, zero otherwise.

Notes

The POSIX function clock_gettime(CLOCK_REALTIME, ts) may also be used to populate a std::timespec with the time since the Epoch.

Example

Run this code

#include <ctime>#include <iostream>   int main(){std::timespec ts; std::timespec_get(&ts, TIME_UTC);char buf[100];std::strftime(buf, sizeof buf, "%D %T", std::gmtime(&ts.tv_sec));std::cout<<"Current time: "<< buf <<'.'<< ts.tv_nsec<<" UTC\n";}

Possible output:

Current time: 06/24/16 20:07:42.949494132 UTC

See also

timespec (C++17)	time in seconds and nanoseconds (struct)
time	returns the current time of the system as time since epoch (function)
C documentation for timespec_get