[plt-scheme] Wake on Lan in Scheme

> (mzscheme already appears to set the SO_BROADCAST option on UDP 
> sockets.)

Ack, correction: this is true if you're using the built-in UDP socket 
stuff in mzscheme.  But I didn't pay attention to the part where you're 
using vyzo's PLaneT socket module.  You should be able to do this using 
the udp socket stuff strictly from mzscheme alone.

But if you're going to use vyzo's module, you'll need to explicitely set 
the SO_BROADCAST stuff as you're doing now, and send to the 
INADDR_BROADCAST address (which will be 255.255.255.255).  See the very 
last example in the socket.plt docs (bottom of the page) for an example of 
UDP broadcast.

     http://planet.plt-scheme.org/package-source/vyzo/socket.plt/1/2/doc.txt