-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hi Jorge, This is exa from #kde :) Using stdin/stdout with ASCII first would be certainly easier. All you have to do is to define some GUI commands. Then if you convert to some binary interface, you could again use either pipes or sockets. I'd referred to this function on irc, but anyway. In posix category. createNamedPipe :: FilePath -> FileMode -> IO () createNamedPipe fifo mode calls mkfifo to create a new named pipe, fifo, with permissions based on mode. And of course you could create that fifo externally with a shell script if you'd like and run stuff from there. I'd almost certainly make it run over stdin/stdout on second thought. You do the connection externally as Sengan says. Create the pipes. fork the program. connect the stdin/stdout of child to your pipes. I think he did it writing C code, but you could also do it using bash, right? #! /bin/sh mkfifo input mkfifo output app <input >output & guifrontend >input