From de1fb253ccf79299a3fec5c7b654436c796093a9 Mon Sep 17 00:00:00 2001
From: Michael Kerrisk <mtk.manpages@gmail.com>
Date: Mon, 22 Nov 2010 08:49:35 +0100
Subject: [PATCH] getgroups.2: Add NOTES explaining 32-bit system calls added
 in Linux 2.4

---
 man2/getgroups.2 | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/man2/getgroups.2 b/man2/getgroups.2
index 9851c8707..39f50946b 100644
--- a/man2/getgroups.2
+++ b/man2/getgroups.2
@@ -28,7 +28,7 @@
 .\" 2008-05-03, mtk, expanded and rewrote parts of DESCRIPTION and RETURN
 .\"     VALUE, made style of page more consistent with man-pages style.
 .\"
-.TH GETGROUPS 2 2008-06-03 "Linux" "Linux Programmer's Manual"
+.TH GETGROUPS 2 2010-11-22 "Linux" "Linux Programmer's Manual"
 .SH NAME
 getgroups, setgroups \- get/set list of supplementary group IDs
 .SH SYNOPSIS
@@ -158,6 +158,16 @@ The maximum number of supplementary group IDs can be found using
 The maximum return value of
 .BR getgroups ()
 cannot be larger than one more than this value.
+
+The original Linux
+.BR getgroups ()
+system call supported only 16-bit group IDs.
+Subsequently, Linux 2.4 added 
+.BR getgroups32 (),
+supporting 32-bit IDs.
+The glibc
+.BR getgroups ()
+wrapper function transparently deals with the variation across kernel versions.
 .SH "SEE ALSO"
 .BR getgid (2),
 .BR setgid (2),