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===================================================================
RCS file: /ftp/cvs/cvsroot/src/bin/expr/expr.1,v
rcsdiff: /ftp/cvs/cvsroot/src/bin/expr/expr.1,v: warning: Unknown phrases like `commitid ...;' are present.
retrieving revision 1.23
retrieving revision 1.24
diff -u -p -r1.23 -r1.24
--- src/bin/expr/expr.1	2003/03/29 18:25:22	1.23
+++ src/bin/expr/expr.1	2003/12/21 10:02:46	1.24
@@ -1,9 +1,40 @@
-.\"	$NetBSD: expr.1,v 1.23 2003/03/29 18:25:22 perry Exp $
+.\"	$NetBSD: expr.1,v 1.24 2003/12/21 10:02:46 jdolecek Exp $
 .\"
-.\" Written by J.T. Conklin <jtc@NetBSD.org>.
-.\" Public domain.
+.\" Copyright (c) 2000,2003 The NetBSD Foundation, Inc.
+.\" All rights reserved.
 .\"
-.Dd September 18, 2000
+.\" This code is derived from software contributed to The NetBSD Foundation
+.\" by J.T. Conklin <jtc@NetBSD.org> and Jaromir Dolecek <jdolecek@NetBSD.org>.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 3. All advertising materials mentioning features or use of this software
+.\"    must display the following acknowledgement:
+.\"        This product includes software developed by the NetBSD
+.\"        Foundation, Inc. and its contributors.
+.\" 4. Neither the name of The NetBSD Foundation nor the names of its
+.\"    contributors may be used to endorse or promote products derived
+.\"    from this software without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
+.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+.\" PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
+.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+.\" POSSIBILITY OF SUCH DAMAGE.
+.\"
+.Dd December 21, 2003
 .Dt EXPR 1
 .Os
 .Sh NAME
@@ -141,6 +172,20 @@ It was rewritten for
 by
 .An Jaromir Dolecek
 .Aq jdolecek@NetBSD.org .
+.Sh NOTES
+Empty string
+.Dq
+cannot be matched with intuitive:
+.Bd -literal -offset indent
+expr '' : '$'
+.Ed
+.Pp
+The reason is the returned number of matched characters (zero)
+is indistinguishable from failed match, so this returns failure.
+To match empty string, use something like:
+.Bd -literal -offset indent
+expr x'' : 'x$'
+.Ed
 .Sh COMPATIBILITY
 This implementation of
 .Nm