From owner-freebsd-current@FreeBSD.ORG  Thu Jan  8 13:15:34 2009
Return-Path: <owner-freebsd-current@FreeBSD.ORG>
Delivered-To: freebsd-current@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id 08B971065670
	for <freebsd-current@freebsd.org>; Thu,  8 Jan 2009 13:15:34 +0000 (UTC)
	(envelope-from jelte@NLnetLabs.nl)
Received: from open.nlnetlabs.nl (open.nlnetlabs.nl [IPv6:2001:7b8:206:1::1])
	by mx1.freebsd.org (Postfix) with ESMTP id 916FF8FC16
	for <freebsd-current@freebsd.org>; Thu,  8 Jan 2009 13:15:33 +0000 (UTC)
	(envelope-from jelte@NLnetLabs.nl)
Received: from mirre.nlnetlabs.nl (mirre.nlnetlabs.nl
	[IPv6:2001:7b8:206:1:219:d1ff:fe0b:89f4]) (authenticated bits=0)
	by open.nlnetlabs.nl (8.14.3/8.14.3) with ESMTP id n08DFP6M094924
	(version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO);
	Thu, 8 Jan 2009 14:15:25 +0100 (CET)
	(envelope-from jelte@NLnetLabs.nl)
Message-ID: <4965FC6D.5090403@NLnetLabs.nl>
Date: Thu, 08 Jan 2009 14:15:25 +0100
From: Jelte Jansen <jelte@NLnetLabs.nl>
User-Agent: Thunderbird 2.0.0.19 (X11/20090105)
MIME-Version: 1.0
To: Damien Fleuriot <dam@c-mal.com>
References: <57dc0bd10901080437y5f745b4ckf40b48a9d9d55ce8@mail.gmail.com>
In-Reply-To: <57dc0bd10901080437y5f745b4ckf40b48a9d9d55ce8@mail.gmail.com>
X-Enigmail-Version: 0.95.2
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 7bit
X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.0
	(open.nlnetlabs.nl [IPv6:2001:7b8:206:1::1]);
	Thu, 08 Jan 2009 14:15:25 +0100 (CET)
X-Spam-Status: No, score=-100.0 required=5.0 tests=NO_RELAYS, USER_IN_WHITELIST
	autolearn=failed version=3.2.5
X-Spam-Checker-Version: SpamAssassin 3.2.5 (2008-06-10) on open.nlnetlabs.nl
Cc: freebsd-current@freebsd.org
Subject: Re: Bug or unwanted behaviour in echo ?
X-BeenThere: freebsd-current@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: Discussions about the use of FreeBSD-current
	<freebsd-current.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-current>, 
	<mailto:freebsd-current-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-current>
List-Post: <mailto:freebsd-current@freebsd.org>
List-Help: <mailto:freebsd-current-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-current>,
	<mailto:freebsd-current-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Thu, 08 Jan 2009 13:15:34 -0000

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Damien Fleuriot wrote:
> 
> After swapping characters around I realized that echo just interprets
> $@ (which in our case is null).
> 

that's your shell doing the replacement, not echo.

With most most shells you can inhibit this behaviour by using single
quotes. Escaping the @ should work in some cases too.

$ echo "abc$@"
abc
$ echo 'abc$@'
abc$@

Jelte
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.9 (FreeBSD)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org

iEYEARECAAYFAkll/G0ACgkQ4nZCKsdOncUSSQCeJuQZi1h+TrKNyxpHmu6hjykO
+mAAnjKGHk76zsyTwwaahKbFWHQvjf1E
=wJHv
-----END PGP SIGNATURE-----