>>> >BTW, you know there *is* a standard ICMP message to let you get the
>>> >local netmask by broadcasting...
>>> 
>>> "Broadcasting to what"? 
>>
>>To the local net.
>>
>>You presumably get answers from the local routers and hosts if they
>>know what the netmask is.
>
>Right, but if you have a CIDR network then the broadcast address is an
>unknown... You could just send the ICMP to the gateway and hope it's
>implemented (is it required by any standards?), but I don't think
>relying on a broadcast is a good idea.

(jumping in over my head perhaps :)

what's wrong with broadcasting to 255.255.255.255?  at a least
configured gatewway should answer, no?

-- 
|-----< "CODE WARRIOR" >-----|
codewarrior@daemon.org             * "ah!  i see you have the internet
twofsonet@graffiti.com (Andrew Brown)                that goes *ping*!"
warfare@graffiti.com      * "information is power -- share the wealth."