[CLUE-Tech] Hex. Cool.

[David Anselmi]

Back in February I played with wake on lan a little.  Here's the start 
of the thread:

http://clue.denver.co.us/pipermail/clue-tech/2002-February/003243.html

One frustration I had was that it wasn't easy to get MAC addresses for 
the machine you want to wake in the binary form that goes out the wire.

I thought I asked at the time, though I can't find it now, how to 
convert ascii hex into bytes.  Turns out there's a utility called xxd 
which seems to come with vim.  Very cool.

You can use this as a binary file editor (or patcher) by dumping the 
file to ascii hex, editing it, and undumping the new file.  You can also 
use it as a less efficient uuencode/uudecode.  A long time ago I saw 
someone send a hex dump of uudecode with a (DOS) debug script to undump 
it (to bootstrap a machine that didn't have uudecode).

Of course a hex dump expands a file at least 2 to 1, while uudecode only 
expands it by 4 to 3.  And btoa is only 5 to 4 (why they picked base 64 
encoding for MIME rather than btoa's base 85 is beyond me).

Dave