The app protocol defines the behaviour of a terminal emulator when opening a
'app://' hyperlink.

The behaviour is basically to send via TCP/IP the given command to the given
hostname and port.

This behaviour can be extracted in a separate program. A terminal emulator
can simply invoke this program, passing it the URI on standard input. This way,
the protocol logic does not need to be hardwired into any terminal emulator.

This package contains the reference implementation of such a handler program.