Date: Mon, 13 May 2024 14:26:23 GMT From: Ed Maste <emaste@FreeBSD.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org Subject: git: c595a834ebbd - stable/13 - clock_gettime.2: Clarify CLOCK_* Message-ID: <202405131426.44DEQNuS021767@gitrepo.freebsd.org>
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The branch stable/13 has been updated by emaste: URL: https://cgit.FreeBSD.org/src/commit/?id=c595a834ebbd4b6fa49b40c8f9cb4e3dda082c4b commit c595a834ebbd4b6fa49b40c8f9cb4e3dda082c4b Author: Mateusz Piotrowski <0mp@FreeBSD.org> AuthorDate: 2022-07-08 19:54:10 +0000 Commit: Ed Maste <emaste@FreeBSD.org> CommitDate: 2024-05-13 14:26:10 +0000 clock_gettime.2: Clarify CLOCK_* Clarify that CLOCK_* (e.g., CLOCK_REALTIME) do not necessarily default to CLOCK_*_FAST. PR: 259642 (cherry picked from commit 16e4487e5f82e1ff501fe5af6afbfbd0435a1cbf) --- lib/libc/sys/clock_gettime.2 | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/lib/libc/sys/clock_gettime.2 b/lib/libc/sys/clock_gettime.2 index 7b325a2bb394..ed469153a40e 100644 --- a/lib/libc/sys/clock_gettime.2 +++ b/lib/libc/sys/clock_gettime.2 @@ -94,19 +94,28 @@ Returns the execution time of the calling thread. .El .Pp The clock IDs +.Fa CLOCK_REALTIME , +.Fa CLOCK_MONOTONIC , +and +.Fa CLOCK_UPTIME +perform a full time counter query. +The clock IDs with the _FAST suffix, i.e., .Fa CLOCK_REALTIME_FAST , .Fa CLOCK_MONOTONIC_FAST , -.Fa CLOCK_UPTIME_FAST -are analogs of corresponding IDs without _FAST suffix but do not perform +and +.Fa CLOCK_UPTIME_FAST , +do not perform a full time counter query, so their accuracy is one timer tick. Similarly, .Fa CLOCK_REALTIME_PRECISE , .Fa CLOCK_MONOTONIC_PRECISE , +and .Fa CLOCK_UPTIME_PRECISE are used to get the most exact value as possible, at the expense of execution time. The clock IDs -.Fa CLOCK_REALTIME_COARSE , +.Fa CLOCK_REALTIME_COARSE +and .Fa CLOCK_MONOTONIC_COARSE are aliases of corresponding IDs with _FAST suffix for compatibility with other systems.
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