[src/trunk]: src/bin/sh Mention what happens when we don't include :. It woul...

[christos <christos%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/f22822a6a801
branches:  trunk
changeset: 770129:f22822a6a801
user:      christos <christos%NetBSD.org@localhost>
date:      Tue Oct 04 18:07:39 2011 +0000

description:
Mention what happens when we don't include :. It would be nice to use
.Dv :
but it produces ``'':

diffstat:

 bin/sh/sh.1 |  8 ++++++--
 1 files changed, 6 insertions(+), 2 deletions(-)

diffs (29 lines):

diff -r 4a4a104a1f9e -r f22822a6a801 bin/sh/sh.1
--- a/bin/sh/sh.1       Tue Oct 04 17:38:00 2011 +0000
+++ b/bin/sh/sh.1       Tue Oct 04 18:07:39 2011 +0000
@@ -1,4 +1,4 @@
-.\"    $NetBSD: sh.1,v 1.103 2011/09/11 06:02:20 dholland Exp $
+.\"    $NetBSD: sh.1,v 1.104 2011/10/04 18:07:39 christos Exp $
 .\" Copyright (c) 1991, 1993
 .\"    The Regents of the University of California.  All rights reserved.
 .\"
@@ -31,7 +31,7 @@
 .\"
 .\"    @(#)sh.1        8.6 (Berkeley) 5/4/95
 .\"
-.Dd June 11, 2011
+.Dd October 4, 2011
 .Dt SH 1
 .Os
 .Sh NAME
@@ -965,6 +965,10 @@
 .Pp
 In addition, a parameter expansion can be modified by using one of the
 following formats.
+If the
+.Dv :
+is omitted in the modifiers, then the expansion is applied only to unset
+parameters, not null ones.
 .Bl -tag -width aaparameterwordaaaaa
 .It ${parameter:-word}
 Use Default Values.