[U-Boot] setting u-boot params based on serial number

[Wolfgang Denk <wd@denx.de>]

Dear "David Collier",

In message <memo.20091026103604.2092e@postmaster+dexdyne.com.cix.co.uk> you wrote:
> > I did not only describe it, I tested it. I just "tricked" a bit.
> > You asked to extract the last two digits, and I used "% 100" to do
> > this. Note that this works correctly in any number base - may it be 
> > 10 or 16 or whatever :-)
> > 
> > Hey, that was clever, wasn't it? :-)
> 
> yeah it was - but of course I really wanted the next 2 digits as well....
> I'm hoping to make more than 100 units really! pardon me for
> over-simplifying my question.

Then do the same with "% 10000" and "/ 100" ?

> I wonder if it would be useful/helpful to allow the user to optionally
> over-ride the number base for reading and separately for writing by
> setexpr.

I don't see a need for it; certainly not here.

> That would extend it's usefulness without requiring an extra command or
> breaking any existing code

No extra command is needed here.

> setenv setexpr_in  10 
> setenv setexpr_out 16
>  
> If I wrote a patch would you look favourably on it?

I don't think so. If we did something like that, it should be generic
and not restricted to one command. And it would break a LOT of
existing scripts. And it is not needed at all, at least not for the
use case you have in mind here. [If anything is worth implementing at
all, then maybe the regexp handling present in standard expr
command.]

Best regards,

Wolfgang Denk

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DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
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