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

[Wolfgang Denk]

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`

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

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