The Application-Layer is the top end of
our Driver model.
Sane calls this Application-Layer the front-end
The only way for an application to access the scanner is the
Command Line Interface
(Be sure you read this before)
This makes it easy to create a scanner-frontends because the
only thing the client-program has to do is to call scanDoX
with a bunch of parameters.
That way any program, that's able to call a linux system command
is able to use the scanner.
The best example for this is InSANE,
the scanner-frontend we are shipping with the driver.
InSANE is a cgi-programm
that is running on an Apache-Webserver.