[U-Boot-Users] [PATCH] Propagate Error Status to the Shell on fw_printenv Errors

[Markus Klotzbücher]

Wolfgang Denk <wd at denx.de> writes:

> In message <87myn2ehqm.fsf at 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`

Oh right, yes. Shouldn't post to lists before drinking coffee in the
morning.

> 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.]

Yes, that would nice indeed. Grant, care to add this? And please update
the documentation in any case.

Best regards

Markus Klotzbücher

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