paste in the fs.posix.setuid blurb from chown(1), as it's

relevant here too;

ok millert

1 files changed, 12 insertions, 1 deletions

diff --git a/bin/chmod/chgrp.1 b/bin/chmod/chgrp.1
index 1210ca71486..b31776304fc 100644
--- a/bin/chmod/chgrp.1
+++ b/bin/chmod/chgrp.1
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: chgrp.1,v 1.15 2014/01/21 15:17:25 jmc Exp $
+.\"	$OpenBSD: chgrp.1,v 1.16 2014/01/21 22:35:44 jmc Exp $
 .\"
 .\" Copyright (c) 1983, 1990, 1993, 1994
 .\"	The Regents of the University of California.  All rights reserved.
@@ -102,6 +102,17 @@ or a numeric group ID.
 If a group name is also a numeric group ID, the operand is used as a
 group name.
 .Pp
+By default,
+.Nm
+clears the set-user-ID and set-group-ID bits on the file
+to prevent accidental or mischievous creation of
+set-user-ID and set-group-ID programs.
+This behaviour can be overridden by setting the
+.Xr sysctl 8
+variable
+.Va fs.posix.setuid
+to zero.
+.Pp
 The user invoking
 .Nm
 must belong to the specified group and be the owner of the file,