From 4b08438c2232533ba1e4fe5c261e699558b46c24 Mon Sep 17 00:00:00 2001
From: Jilles Tjoelker <jilles@FreeBSD.org>
Date: Fri, 31 May 2013 22:09:31 +0000
Subject: [PATCH] dup(2): Clarify return value, in particular of dup2().

---
 lib/libc/sys/dup.2 | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/lib/libc/sys/dup.2 b/lib/libc/sys/dup.2
index 7b36d273115f..4254b9e72812 100644
--- a/lib/libc/sys/dup.2
+++ b/lib/libc/sys/dup.2
@@ -28,7 +28,7 @@
 .\"     @(#)dup.2	8.1 (Berkeley) 6/4/93
 .\" $FreeBSD$
 .\"
-.Dd April 21, 2013
+.Dd June 1, 2013
 .Dt DUP 2
 .Os
 .Sh NAME
@@ -113,10 +113,11 @@ is a valid descriptor, then
 .Fn dup2
 is successful, and does nothing.
 .Sh RETURN VALUES
-The value -1 is returned if an error occurs in either call.
-The external variable
+These calls return the new file descriptor if successful;
+otherwise the value -1 is returned and
+the external variable
 .Va errno
-indicates the cause of the error.
+is set to indicate the cause of the error.
 .Sh ERRORS
 The
 .Fn dup