On Thu, Jul 15, 2010 at 12:00:04PM +0200, 
[email protected] wrote:
> Hey all I have a big problem with openwrt!
> 
> In a bash shell if i write this command
> printf "%d\n" "`echo "255.255.255.255" | awk -F\. '{printf "%d",
> ($4)+($3*256)+($2*256*256)+($1*256*256*256)}'`"
> i obtain
> 2147483647
> that is wrong!

The question here would be WHAT exactly is wrong here ;)
Probably not this shell...

%d is a format string for a _signed_ integer, not the unsigned
expression that is being evaluated here.
And with common systems an integer value is specified as 32bit,
resulting in this INT_MAX value for any values _larger_ than that.

> If i put the same command in my gentoo bash shell i obtain  4294967295 that
> is the good value how to fix this ?

%u would fix that, or perhaps better use %lu (or better %llu?) for
higher probability to get the correct value.
OTOH since an IPv4 address will always remain 32bit, %u is fully
sufficient and thus the exactly adapted and proper solution.

HTH,

Andreas Mohr
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