9p filesystem for searching a remote directory.

This fileserver provides an RPC endpoint to search a remote filesystem.

Start it on your remote fileserver in a listener

	aux/listen1 tcp!*!1234 grepfs /path/to/files/*

Then you can connect to it with whatever 9p client you use. For unix, I recommend 9pfs! For plan 9 you connect to it like normal:

	srv tcp!remote!1234 grepfs
	mount -a /srv/grepfs .

This will put in your directory a single file:

	grepctl

that accepts regular expressions as follows:

	echo -n regex > grepctl

That calls grep on the remote server in the directory provided with the regular expression "regex" that you provided. The results are returned by reading the same file:

	cat dirnamegrep

The following script is helpful:

#!/bin/rc
echo -n $1 > grepctl
cat grepctl