From owner-freebsd-current  Tue Feb 18  3:39:28 2003
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To: current@freebsd.org
Subject: Shell programming 101:  Is this an expr(1) bug ?
From: Poul-Henning Kamp <phk@phk.freebsd.dk>
Date: Tue, 18 Feb 2003 12:39:22 +0100
Message-ID: <57374.1045568362@critter.freebsd.dk>
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Running:

	#!/bin/sh
	set -ex

	for p in ad2 ad0 ad1
	do
		a0=`expr $p : '^ad\([0-9]\)$'`
	done

I get:

	syv# sh _
	+ expr ad2 : ^ad\([0-9]\)$
	+ a0=2
	+ expr ad0 : ^ad\([0-9]\)$
	+ a0=0
	syv# echo $?
	1
	syv# 

That looks like a bug to me...

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe
Never attribute to malice what can adequately be explained by incompetence.

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