From mboxrd@z Thu Jan  1 00:00:00 1970
From: Wolfgang Denk <wd@denx.de>
Date: Wed, 07 May 2008 09:10:06 +0200
Subject: [U-Boot-Users] [PATCH] Propagate Error Status to the Shell on
	fw_printenv Errors
In-Reply-To: Your message of "Wed, 07 May 2008 08:44:01 +0200."
	<87myn2ehqm.fsf@denx.de>
Message-ID: <20080507071007.0818A2477F@gemini.denx.de>
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In message <87myn2ehqm.fsf@denx.de> you wrote:
> 
> > 	root at kilauea# fw_printenv -n hostname ipaddr
> > 	## Error: `-n' option requires exactly one argument
> > 	root at kilauea# echo $?
> > 	1
> 
> But I don't understand what the purpose of the "-n" option is?

The purpose seems clear to me - print the value of a variable without
the name. This can be useful in shell scripts, for example when you
want to do something like

	$ ipaddr=`fw_printenv -n ipaddr`

However, the addition of this feature is undocumented (not mentioned
in the commit message), and I don;t see why we should restrict it to a
single variable - it may be useful to print several values here, too,
for example like that:

	$ set `fw_printenv -n netdev ipaddr netmask`
	$ ifconfig $1 $2 netmask $3

[Well, I know that's a bad example because  it's  missing  all  error
checking, but you get the idea.]

Best regards,

Wolfgang Denk

-- 
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
It is impractical for  the  standard  to  attempt  to  constrain  the
behavior  of code that does not obey the constraints of the standard.
                                                          - Doug Gwyn