ORCHARD/BRUC@SCARECROW.WAISMAN.WISC.EDU (Bruce Orchard) (02/17/88)
I have debugged Postscript programs in 3 ways:
1. Run blind, as you describe (sometimes just getting a blank
sheet is a major advance).
2. I modified the spooler on the system passing Postscript
to the Apple Laserwriter to log any messages it received
from the Laserwriter along with the line number in the
file. Due to buffering, the line number displayed will
be beyond the real error, but probably not more than
about 20 lines. (Anyone who wants my spooler is welcome
to it, but it is for a Harris H800 running VOS and requires
some messy changes to VOS. The idea applies to any spooler.)
3. Drive the Laserwriter from a terminal emulator program
on the supplying system. Put the Postscript in a file and
tell the terminal emulator program to send the file.
I run the Laserwriter in interactive mode rather than batch mode
so that the Postscript gets echoed by the Laserwriter and
the error messages come out right after the offending statement.
(I did it without running XOFF/XON. I had the terminal emulator
program put in a long (.5 second, I think) delay after each
carriage return.)
Bruce Orchard