git: b7e90b290ab5 - stable/13 - kqueue: document how timers with low/past timeouts are handled

From: Kyle Evans <>
Date: Wed, 06 Oct 2021 07:04:38 UTC
The branch stable/13 has been updated by kevans:


commit b7e90b290ab511dbbf1f1598e49092aaa73599e6
Author:     Kyle Evans <>
AuthorDate: 2021-09-30 18:19:05 +0000
Commit:     Kyle Evans <>
CommitDate: 2021-10-06 07:04:00 +0000

    kqueue: document how timers with low/past timeouts are handled
    (cherry picked from commit 4b5554cebb66020f59dc869b835aebbd66e4bb8c)
 lib/libc/sys/kqueue.2 | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/lib/libc/sys/kqueue.2 b/lib/libc/sys/kqueue.2
index ed737c626ef8..ffcddc00303f 100644
--- a/lib/libc/sys/kqueue.2
+++ b/lib/libc/sys/kqueue.2
@@ -24,7 +24,7 @@
 .\" $FreeBSD$
-.Dd September 7, 2021
+.Dd October 6, 2021
@@ -584,6 +584,12 @@ On return,
 .Va fflags
 contains the events which triggered the filter.
+Periodic timers with a specified timeout of 0 will be silently adjusted to
+timeout after 1 of the time units specified by the requested precision in
+.Va fflags .
+If an absolute time is specified that has already passed, then it is treated as
+if the current time were specified and the event will fire as soon as possible.
 If an existing timer is re-added, the existing timer will be
 effectively canceled (throwing away any undelivered record of previous
 timer expiration) and re-started using the new parameters contained in