timespec_get

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Compiler support
Language
Headers
Type support
Program utilities
Variadic function support
Error handling
Dynamic memory management
Strings library
Algorithms
Numerics
Date and time utilities
Input/output support
Localization support
Concurrency support(C11)
Technical Specifications
Symbol index

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Date and time utilities

Functions
Time manipulation
difftime
time
clock
timespec_get (C11)
timespec_getres (C23)
Format conversions
asctimeasctime_s (deprecated in C23)(C11)
ctimectime_s (deprecated in C23)(C11)
strftime
wcsftime (C95)
gmtimegmtime_rgmtime_s (C23)(C11)
localtimelocaltime_rlocaltime_s (C23)(C11)
mktime
Constants
CLOCKS_PER_SEC
Types
tm
time_t
clock_t
timespec (C11)

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Defined in header`<time.h>`
int timespec_get(struct timespec*ts,int base);	(1)	(since C11)
#define TIME_UTC /* implementation-defined */	(2)	(since C11)

1) Modifies thetimespec object pointed to byts to hold the current calendar time in the time basebase.

2) Expands to a value suitable for use as thebase argument oftimespec_get

Other macro constants beginning withTIME_ may be provided by the implementation to indicate additional time bases

Ifbase isTIME_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

[edit]Parameters

ts	-	pointer to an object of typestruct timespec
base	-	`TIME_UTC` or another nonzero integer value indicating the time base

[edit]Return value

The value ofbase if successful, zero otherwise.

[edit]Notes

The POSIX functionclock_gettime(CLOCK_REALTIME, ts) may also be used to populate atimespec with the time since the Epoch.

[edit]Example

Run this code

#include <stdio.h>#include <time.h> int main(void){struct timespec ts;    timespec_get(&ts, TIME_UTC);char buff[100];strftime(buff,sizeof buff,"%D %T",gmtime(&ts.tv_sec));printf("Current time: %s.%09ld UTC\n", buff, ts.tv_nsec);}

Possible output:

Current time: 02/18/15 14:34:03.048508855 UTC

[edit]References

C23 standard (ISO/IEC 9899:2024):

7.27.2.5 The timespec_get function (p: TBD)

C17 standard (ISO/IEC 9899:2018):

7.27.2.5 The timespec_get function (p: 286)

C11 standard (ISO/IEC 9899:2011):

7.27.2.5 The timespec_get function (p: 390)

[edit]See also

timespec (C11)	time in seconds and nanoseconds (struct)[edit]
timespec_getres (C23)	returns the resolution of calendar time based on a given time base (function)[edit]
time	returns the current calendar time of the system as time since epoch (function)[edit]
C++ documentation fortimespec_get