< c‎ | chrono
Defined in header <time.h>
int timespec_getres( struct timespec *ts, int base );
(since C23)

If ts is non-null and base is supported by timespec_get, modifies *ts to hold the resolution of time provided by timespec_get for base. For each supported base, multiple calls to timespec_getres during the same program execution have identical results.


[edit] Parameters

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

[edit] Return value

The value of base if base is supported, zero otherwise.

[edit] Notes

The POSIX function clock_getres(clock_id, ts) may also be used to populate a timespec with the resolution of time identified by clock_id.

[edit] Example

#include <stdio.h>
#include <time.h>
int main(void)
    char buff[128];
    struct timespec ts;
    const int res = timespec_getres(&ts, TIME_UTC);
    if (res == TIME_UTC) {
        struct tm timer;
        strftime(buff, sizeof buff, "%D %T", gmtime_r(&ts.tv_sec, &timer));
        printf("Time resolution info: %s.%09ld UTC\n", buff, ts.tv_nsec);
    } else {
        printf("TIME_UTC base is not supported.");

Possible output:

Time resolution info: 01/01/70 00:00:00.000000001 UTC

[edit] See also

time in seconds and nanoseconds
(struct) [edit]
returns the calendar time based on a given time base
(function) [edit]
returns the current calendar time of the system as time since epoch
(function) [edit]