🚀 go-pugleaf

In article <3944@ecicrl.ocunix.on.ca> clewis@ferret.ocunix.on.ca (Chris Lewis) writes:

>>When printing from MS Windows to Postscript file, the file (if you don't
>>make it not to) starts with characters ^D%! (i.e. control-D, %, !).

>The correct way to handle this is for the application to *not*
>append or prepend ^D's, and let the spooler handle it.

Errr, since when does MS Windows *have* a print spooler?  Don't you
think it would be pretty silly of the applications to generate output
that wouldn't work under the most common conditions?

>MS Windows use of ^D is a kludge workaround for somebody else's botch.
>A bad kludge.  Because the output of MS Windows ain't PostScript because
>of it.

Yes, having a single-tasking operating system is a botch I suppose, but
it happens a lot in the real world.  I say the botch is that postscript
printers require the ^D  to terminate a job over the serial/parallel
ports, yet it isn't a defined postscript command.  Personal computers
typically output directly to the printer generally do not provide
graceful termination when you cancel a print job or shut the machine
down. Thus applications cannot assume that the previous job was correctly
terminated and that the printer is in the correct state to start another
one without a ^D to flush it.  The same applies to printing to files
under DOS/windows since the most likely use of those files is to simply
copy them to the printer device.

If ^D or some other token (perhaps not in the control character range) had
been included in the postscript language definition to perform this needed
function the problem simply wouldn't exist.  In fact it could have been
documented like showpage as an operator that should be redefined during
EPS inclusion.  As things stand, I think the best approach is to teach
print spoolers to ignore leading ^D's on postscript documents.  Otherwise
it's impossible to get consistent behaviour when alternating between a
direct connection to a postscript printer and a network link that ends
up going through a print spooler.

Les Mikesell
  les@chinet.chi.il.us