On 2026-01-29T08:52:23-0800, Mark Harris wrote:
> Add Feature Test Macro Requirements to document functions and macros
> that require ISO C11 or C23, and arrange supported time bases as a list.
> 
> Signed-off-by: Mark Harris <mark.hsj@gmail.com>

Patch applied; thanks!


Cheers,
Alex

> ---
> v3: Use .TQ for time bases in STANDARDS and HISTORY
> v2: Split into two patches, add time bases to History section
> 
>  man/man3/timespec_get.3 | 25 ++++++++++++++++++++++---
>  1 file changed, 22 insertions(+), 3 deletions(-)
> 
> diff --git a/man/man3/timespec_get.3 b/man/man3/timespec_get.3
> index 79bb82226..67da4858c 100644
> --- a/man/man3/timespec_get.3
> +++ b/man/man3/timespec_get.3
> @@ -17,6 +17,22 @@ .SH SYNOPSIS
>  .BI "int timespec_get(struct timespec *" res ", int " base );
>  .BI "int timespec_getres(struct timespec *" tp ", int " base );
>  .fi
> +.P
> +.RS -4
> +Feature Test Macro Requirements for glibc (see
> +.BR feature_test_macros (7)):
> +.RE
> +.P
> +.BR timespec_get (),
> +.BR TIME_UTC :
> +.nf
> +    _ISOC11_SOURCE
> +.fi
> +.P
> +.BR timespec_getres ():
> +.nf
> +    _ISOC23_SOURCE
> +.fi
>  .SH DESCRIPTION
>  The
>  .BR timespec_get ()
> @@ -39,16 +55,18 @@ .SH DESCRIPTION
>  For a particular time base,
>  the resolution is constant for the lifetime of the calling process.
>  .P
> +The time base
> +.I base
> +is one of the following:
> +.TP
>  .B TIME_UTC
> -is always a supported time base,
> -and is the only time base supported on Linux.
> +A system-wide time base that measures real (i.e., wall-clock) time.
>  The time and resolution in this time base
>  are the same as those retrieved by
>  .I clock_gettime(CLOCK_REALTIME,\~res)
>  and
>  .IR clock_getres(CLOCK_REALTIME,\~tp) ,
>  respectively.
> -Other systems may support additional time bases.
>  .SH RETURN VALUE
>  .BR timespec_get ()
>  returns the nonzero
> @@ -78,6 +96,7 @@ .SH ATTRIBUTES
>  .SH STANDARDS
>  .TP
>  .BR timespec_get ()
> +C23, POSIX.1-2024.
>  .TQ
>  .B TIME_UTC
>  C23 (though ISO C doesn't specify the time epoch),
> -- 
> 2.52.0
> 
> 

-- 
<https://www.alejandro-colomar.es>