From 10b1416d2fa79070dc8b6a6498d19a3eaa20d313 Mon Sep 17 00:00:00 2001
From: David Schultz <das@FreeBSD.org>
Date: Sun, 8 Feb 2004 12:38:30 +0000
Subject: [PATCH] Update the documentation for setpgrp(2) to reflect the access
 control checks that the code actually performs.  Judging from the 4.2BSD
 release notes, the docs have only been out of date for 20 years.

PR:	29844
---
 lib/libc/sys/setpgid.2 | 28 +++++++++++++++++++++-------
 1 file changed, 21 insertions(+), 7 deletions(-)

diff --git a/lib/libc/sys/setpgid.2 b/lib/libc/sys/setpgid.2
index 37c1d987302..c771e0377aa 100644
--- a/lib/libc/sys/setpgid.2
+++ b/lib/libc/sys/setpgid.2
@@ -32,7 +32,7 @@
 .\"     @(#)setpgid.2	8.1 (Berkeley) 6/4/93
 .\" $FreeBSD$
 .\"
-.Dd June 4, 1993
+.Dd February 8, 2004
 .Dt SETPGID 2
 .Os
 .Sh NAME
@@ -59,9 +59,12 @@ If
 .Fa pid
 is zero, then the call applies to the current process.
 .Pp
-If the invoker is not the super-user, then the affected process
-must have the same effective user-id as the invoker or be a descendant
-of the invoking process.
+If the affected process is not the invoking process, then it must be a
+child of the invoking process, it must not have performed an
+.Xr exec 3
+operation, and both processes must be in the same session.
+The requested process group ID must already exist in the session of
+the caller, or it must be equal to the target process ID.
 .Sh RETURN VALUES
 .Rv -std setpgid
 .Sh ERRORS
@@ -70,12 +73,23 @@ The
 system call
 will fail and the process group will not be altered if:
 .Bl -tag -width Er
+.It Bq Er EINVAL
+The requested process group ID is not legal.
 .It Bq Er ESRCH
 The requested process does not exist.
+.It Bq Er ESRCH
+The target process is not the calling process or
+a child of the calling process.
+.It Bq Er EACCES
+The requested process is a child of the calling process,
+but it has performed an
+.Xr exec 3
+operation.
 .It Bq Er EPERM
-The effective user ID of the requested process is different
-from that of the caller and the process is not a descendent
-of the calling process.
+The target process is a session leader.
+.It Bq Er EPERM
+The requested process group ID is not in the session of the caller,
+and it is not equal to the process ID of the target process.
 .El
 .Sh SEE ALSO
 .Xr getpgrp 2