software page accounting and apsfilter

[Michal Szymanski <msz@xxxxxxxxxxxxxx>]

Hi,

I wonder how easy (or how difficult :) would it be to implement software
page accounting into apsfilter setup.

I know, I know. Hardware page accounting is better. Yes it is. But it
does not work :-))) At least for me. I've tried both a HP2100 PS printer
on a parallel port and a Lexmark Optra 1650S on another parallel port,
both with no success. Surely I won't change to serial connection (which
is said to work better for two-ways communication) only for that
purpose. Moreover, HP2100 does not even have serial interface.

On the other hand, most (if not all) jobs printed by these printers are
PS jobs. AFAIK, pipelining a PS file through "psnup" program with no
options does not change anything (or, better to say, anything important)
in the PS source but produces a nice 'stderr' output containing the
number of pages processed. In principle, it should be straightforward to
grab this 'stderr' output and making a nice accounting entry.

The only problem is to insert this "psnup" and 'stderr' grabbing into
the apsfilter pipeline in a way that would not screw up other things.
So, a question to experts: how can one do it nicely? Maybe even
apsfilter is already prepared and has an option to add extra "user
filter" into the pipeline?

regards, Michal.

-- 
  Michal Szymanski (msz@astrouw.edu.pl)
  Warsaw University Observatory, Warszawa, POLAND