Bad PostScript data generated -- any way to diagnose?

[Helge Blischke]

Alex Taylor wrote:

> On Fri, 15 Oct 2010 11:12:17 UTC, Helge Blischke <h.blischke at acm.org>
> wrote:
> 
>> > The problem is that running the file through CUPS results in an
>> > unprintable file.  Here is the output of the same file, immediately
>> > after being processed by pstops and foomatic-rip:
>> >   http://users.socis.ca/~ataylo00/output_ps_bad.zip  (114 KB)
>> 
>> isn't this just the case we fiddled around about a month ago (the OS/2
>> issue)?
> 
> Yes, although with somewhat farther-evolved diagnosis on my part.  As
> posted on .development, I thought it best to move the thread to the
> .general list.
> 
> 
>> If you - as a test - edit the foomatic-rip.ps and comment out the end
>> statement immediately preceding the showpage (i. e. prepend a % the the
>> end), it will be rendered by ghostscript (yes, even 9.00) and print OK
>> on a real printer (a OKI C3600 in my case).
> 
> Indeed, the generated output file looks much cleaner now.  (I can't
> actually test printing it until Monday, when I'm back at work...)
> 
> 
>> The reason for the failure is that the setup section (the first one)
>> contains a  a "200 dict begin" near the beginning (to be precise, in
>> line 99), and this (anonymous) dictionary is popped off from the
>> dictionary stack just preceding the showpage statement.
> 
> OK.  Given my near-zero level knowledge of PostScript, I'll have to
> take your word for that. <g>
> 
>> I think as you may not be able to modify the presentation manager of
>> OS/2, the only way to settle this issue is to implement a prefilter in
>> CUPS for the file type "application/postscript" that checks for
>> %%Creator: Presentation Manager and, if true, edits the PS file
>> appropriately.
> 
> Actually, we do have the source code for the PostScript presentation
> driver; we've already made some minor modifications to it, so this
> may well be within our powers as well. :)
Do you think it would be possible to send me the respective sources to have 
a look into? Though I do not have an OS/2 here I think it may be possible to 
propose the necessary modifications.
> 
> 
>> In order to know what to do in detail I'd need to know how jobs look
>> like that contain more than only one page.
> 
> I'll try and produce one shortly.
> 
> Thanks!
> 

Helge