diff --git a/bin/timeout/timeout.1 b/bin/timeout/timeout.1
index 43a484dac76f..6486ccf99a36 100644
--- a/bin/timeout/timeout.1
+++ b/bin/timeout/timeout.1
@@ -1,263 +1,292 @@
 .\" SPDX-License-Identifier: BSD-2-Clause
 .\"
 .\" Copyright (c) 2014 Baptiste Daroussin <bapt@FreeBSD.org>
+.\" Copyright (c) 2025 Aaron LI <aly@aaronly.me>
 .\" All rights reserved.
 .\"
 .\" Redistribution and use in source and binary forms, with or without
 .\" modification, are permitted provided that the following conditions
 .\" are met:
 .\" 1. Redistributions of source code must retain the above copyright
 .\"    notice, this list of conditions and the following disclaimer.
 .\" 2. Redistributions in binary form must reproduce the above copyright
 .\"    notice, this list of conditions and the following disclaimer in the
 .\"    documentation and/or other materials provided with the distribution.
 .\"
 .\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 .\" ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
 .Dd April 3, 2025
 .Dt TIMEOUT 1
 .Os
 .Sh NAME
 .Nm timeout
 .Nd run a command with a time limit
 .Sh SYNOPSIS
 .Nm
 .Op Fl f | Fl -foreground
 .Op Fl k Ar time | Fl -kill-after Ar time
 .Op Fl p | Fl -preserve-status
 .Op Fl s Ar signal | Fl -signal Ar signal
 .Op Fl v | Fl -verbose
 .Ar duration
 .Ar command
 .Op Ar arg ...
 .Sh DESCRIPTION
 .Nm Timeout
 starts the
 .Ar command
 with its
 .Ar arg
 list.
 If the
 .Ar command
 is still running after
 .Ar duration ,
 it is killed by sending the
 .Ar signal ,
 or
 .Dv SIGTERM
 if the
 .Fl s
 option is unspecified.
 The special
 .Ar duration ,
 zero, signifies no limit.
 Therefore, a signal is never sent if
 .Ar duration
 is 0.
 .Pp
 The signal dispositions inherited by the
 .Ar command
 are the same as the dispositions that
 .Nm
 inherited, except for the signal that will be sent upon timeout,
 which is reset to take the default action and should terminate
 the process.
 .Pp
 If
 .Nm
 receives the
 .Dv SIGALRM
 signal, it will behave as if the time limit has been reached
 and send the specified signal to
 .Ar command .
 For any other signals delivered to
 .Nm ,
 it will propagate them to
 .Ar command ,
 with the exception of
 .Dv SIGKILL
 and
 .Dv SIGSTOP .
 If you want to prevent the
 .Ar command
 from being timed out, send
 .Dv SIGKILL
 to
 .Nm .
 .Pp
 The options are as follows:
 .Bl -tag -width indent
 .It Fl f , Fl -foreground
 Only time out the
 .Ar command
 itself, but do not propagate signals to its descendants.
+See the
+.Sx IMPLEMENTATION NOTES
+section for more details.
 .It Fl k Ar time , Fl -kill-after Ar time
 Send a
 .Dv SIGKILL
 signal if
 .Ar command
 is still running after
 .Ar time
 since the first signal was sent.
 .It Fl p , Fl -preserve-status
 Always exit with the same status as
 .Ar command ,
 even if the timeout was reached.
 .It Fl s Ar signal , Fl -signal Ar signal
 Specify the signal to send on timeout.
 By default,
 .Dv SIGTERM
 is sent.
 .It Fl v , Fl -verbose
 Show information to
 .Xr stderr 4
 about timeouts, signals to be sent, and the
 .Ar command
 exits.
 .El
 .Ss Duration Format
 The
 .Ar duration
 and
 .Ar time
 are non-negative integer or real (decimal) numbers, with an optional
 suffix specifying the unit.
 Values without an explicit unit are interpreted as seconds.
 .Pp
 Supported unit suffixes are:
 .Bl -tag -offset indent -width indent -compact
 .It Cm s
 seconds
 .It Cm m
 minutes
 .It Cm h
 hours
 .It Cm d
 days
 .El
+.Sh IMPLEMENTATION NOTES
+If the
+.Fl -foreground
+option is not specified,
+.Nm
+runs as the reaper (see also
+.Xr procctl 2 )
+of the
+.Ar command
+and its descendants, and will wait for all the descendants to terminate.
+This behavior might cause surprises if there are descendants running
+in the background, because they will ignore
+.Dv SIGINT
+and
+.Dv SIGQUIT
+signals.
+For example, the following command that sends a
+.Dv SIGTERM
+signal will complete in 2 seconds:
+.Dl $ timeout -s TERM 2 sh -c 'sleep 4 & sleep 5'
+However, this command that sends a
+.Dv SIGINT
+signal will complete in 4 seconds:
+.Dl $ timeout -s INT 2 sh -c 'sleep 4 & sleep 5'
 .Sh EXIT STATUS
 If the time limit was reached and the
 .Fl -preserve-status
 option is not specified, the exit status is 124.
 Otherwise,
 .Nm
 exits with the same exit status as the
 .Ar command .
 For example,
 .Nm
 will terminate itself with the same signal if the
 .Ar command
 is terminated by a signal.
 .Pp
 If an error occurred, the following exit values are returned:
 .Bl -tag -offset indent with indent -compact
 .It 125
 An error other than the two described below occurred.
 For example, an invalid duration or signal was specified.
 .It 126
 The
 .Ar command
 was found but could not be executed.
 .It 127
 The
 .Ar command
 could not be found.
 .El
 .Sh EXAMPLES
 Run
 .Xr sleep 1
 with a time limit of 4 seconds.
 Since the command completes in 2 seconds, the exit status is 0:
 .Bd -literal -offset indent
 $ timeout 4 sleep 2
 $ echo $?
 0
 .Ed
 .Pp
 Run
 .Xr sleep 1
 for 4 seconds and terminate process after 2 seconds.
 The exit status is 124 since
 .Fl -preserve-status
 is not used:
 .Bd -literal -offset indent
 $ timeout 2 sleep 4
 $ echo $?
 124
 .Ed
 .Pp
 Same as above but preserving status.
 The exit status is 128 + signal number (15 for
 .Dv SIGTERM )
 for most shells:
 .Bd -literal -offset indent
 $ timeout --preserve-status 2 sleep 4
 $ echo $?
 143
 .Ed
 .Pp
 Same as above but sending
 .Dv SIGALRM
 (signal number 14) instead of
 .Dv SIGTERM :
 .Bd -literal -offset indent
 $ timeout --preserve-status -s SIGALRM 2 sleep 4
 $ echo $?
 142
 .Ed
 .Pp
 Try to
 .Xr fetch 1
 the PDF version of the
 .Fx
 Handbook.
 Send a
 .Dv SIGTERM
 signal after 1 minute and send a
 .Dv SIGKILL
 signal 5 seconds later if the process refuses to stop:
 .Bd -literal -offset indent
 $ timeout -k 5s 1m fetch \\
 > https://download.freebsd.org/ftp/doc/en/books/handbook/book.pdf
 .Ed
 .Sh SEE ALSO
 .Xr kill 1 ,
 .Xr nohup 1 ,
 .Xr signal 3 ,
 .Xr daemon 8
 .Sh STANDARDS
 The
 .Nm
 utility is expected to conform to the
 .St -p1003.1-2024
 specification.
 .Sh HISTORY
 The
 .Nm
 command first appeared in
 .Fx 10.3 .
 .Pp
-The
+The initial
 .Fx
-work is compatible with GNU
+work was compatible with GNU
 .Nm
 by
 .An Padraig Brady ,
 from GNU Coreutils 8.21.
 The
 .Nm
 utility first appeared in GNU Coreutils 7.0.
 .Sh AUTHORS
-.An Baptiste Daroussin Aq Mt bapt@FreeBSD.org
-and
+.An Baptiste Daroussin Aq Mt bapt@FreeBSD.org ,
 .An Vsevolod Stakhov Aq Mt vsevolod@FreeBSD.org
+and
+.An Aaron LI Aq Mt aly@aaronly.me