git: f08af2491ffd - stable/14 - adjtime(2): document that delta can be NULL

The branch stable/14 has been updated by kevans:

URL: https://cgit.FreeBSD.org/src/commit/?id=f08af2491ffd603f571b2cd5c7f1fe0cab603a10

commit f08af2491ffd603f571b2cd5c7f1fe0cab603a10
Author:     Kyle Evans <kevans@FreeBSD.org>
AuthorDate: 2026-06-20 13:55:26 +0000
Commit:     Kyle Evans <kevans@FreeBSD.org>
CommitDate: 2026-08-06 22:52:25 +0000

    adjtime(2): document that delta can be NULL
    
    The current verbiage somewhat indicates that always adjusts the time,
    which hasn't been true as far back as I had the energy to `git blame`.
    
    Reviewed by:    imp
    
    (cherry picked from commit 8ed580b1d3811e73e25db3d8a9fd235156c65387)
---
 lib/libc/sys/adjtime.2 | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/lib/libc/sys/adjtime.2 b/lib/libc/sys/adjtime.2
index e1957ace66b6..02123e9c4ef0 100644
--- a/lib/libc/sys/adjtime.2
+++ b/lib/libc/sys/adjtime.2
@@ -27,7 +27,7 @@
 .\"
 .\"     @(#)adjtime.2	8.1 (Berkeley) 6/4/93
 .\"
-.Dd May 13, 2021
+.Dd June 19, 2026
 .Dt ADJTIME 2
 .Os
 .Sh NAME
@@ -48,6 +48,7 @@ makes small adjustments to the system time, as returned by
 advancing or retarding it
 by the time specified by the timeval
 .Fa delta .
+.Pp
 If
 .Fa delta
 is negative, the clock is
@@ -57,6 +58,13 @@ If
 .Fa delta
 is positive, a larger increment than normal
 is used.
+.Fa delta
+may also be a
+.Dv NULL
+pointer to fetch
+.Fa olddelta
+without making any adjustment.
+.Pp
 The skew used to perform the correction is generally a fraction of one percent.
 Thus, the time is always
 a monotonically increasing function.
@@ -67,7 +75,9 @@ may not be finished when
 is called again.
 If
 .Fa olddelta
-is not a null pointer,
+is not a
+.Dv NULL
+pointer,
 the structure pointed to will contain, upon return, the
 number of microseconds still to be corrected
 from the earlier call.