Exec in Response to Remote String

[Caylan Larson]

I'm using GNU screen to connect to a VT100 terminal server (DOS running in 
DOSEMU). I want to configure custom strings to exec a subprocess. This would be 
similar to printcmd, except I would return the processes STDOUT to the remote 
server's STDIN (and I'd get to choose my own start/stop sequences). I've read 
the GNU screen manual and understand the basics of exec, but I don't know how 
to make the exec happen on remote escape sequences.  Is this possible?

Caylan