printing using CUPS' drivers

[Ben Abbott]

During the discussion on the help-list below, I realized that there is a 
problem with your print.m does its task

        https://www-old.cae.wisc.edu/pipermail/help-octave/2010-May/019745.html

There is an implied conflict between Octave's use of ghostscript and the use of 
the CUPS drivers in unix systems.

Consider three examples for how printing may be handled using lpr.

(1) For postscript printers

        lpr -l myfile.ps

(2) For non-postscript printers using ghostscript, an Epson printer for example

        gs -sDEVICE=epson sOutputFile=foo.bar myfile.ps
        lpr -l foo.bar

(3) To print using the CUPS drivers

        lpr myfile.ps

In some cases, when using the 3rd approach with a postscript printer many pages 
of postscript code will be printed (i.e. the postscript is filtered as if it 
were ascii). 

With the "-l" option (equiv to "-o raw") is used with a non-postscript printer, 
the output is either nothing or (again) several pages of postscript code.

Should a preference be used to select between the system filter and 
ghostscript? ... or should print.m be modified to allow the lpr options to be 
explicitly specified? ... or something else?

Ben