Path: utzoo!attcan!uunet!samsung!zaphod.mps.ohio-state.edu!uwm.edu!bionet!apple!well!shiva
From: shiva@well.sf.ca.us (Kenneth Porter)
Newsgroups: comp.lang.postscript
Subject: Re: PostScript vs TrueType?
Summary: NEC LC890 Bug Test (comment detection loop)
Message-ID: <20146@well.sf.ca.us>
Date: 6 Sep 90 07:49:24 GMT
References: <9724@goofy.Apple.COM> <438@three.mv.com> <9931@goofy.Apple.COM> <1513@chinacat.Unicom.COM>
Lines: 66



Woody posted code containing the following fragment as an
example of something that would hang an NEC LC890, with the
request that fellow LC890 owners would test it.
 
{
	currentfile(   )readstring
	{
		(%%%)eq		%look for separator
		{
			exit
		}if
	}
	{
		pop		%hangs, looking forever
	}ifelse
}loop
%
% ...bunch of PostScript code to skip over...
%
%%%%%%
 
Sorry, Woody, but your LC890 file works just fine on my LC890.
It finds the (%%%) and exits.  I put the test in foo.ps and did
"cat foo.ps foo.ps | lpr" and got a standard EOF indication
back. I even put prints in the exit and pop paths of the loop
to verify which was taken and the comment detection path *was*
taken.  I also cat-ed two copies of your complete font example
and got the same result.
 
Just so we agree on versions, here's a dump of some stats from
the printer:
 
Product: Silentwriter
Version: 47.0
Revision: 1
Printer Name: Silentwriter
Pagecount: 24432
Do Start Page: true
Margins: -16 25
Default Paper Tray: 2
Default Timeouts: 0 60 30
Usertime: 581751454
VM Total: 1318576
VM Used:  544622
VM Available: 773954
Save Level: 2
 
Perhaps there's something odd about your host setup.  What do
you use to send files?  If a unix spooler, what filters are
involved?  Could a filter in the host be stripping your
comments or adding unexpected newlines?
 
Incidentally, I noted that the code fragment was saving the
packing flag and packing the font.  Users of Presentation
Manager should be aware that the PM PostScript prolog is
ignorant of the packing flag and writes a dictionary into a
procedure body to get local variables in a private dictionary:
 
/BuildChar { 0 begin ... end } def
BuildChar load 0 3 dict put
 
This means that you can't set packing on by default when using
PM or the above trick will cause an invalidaccess as the put
stores into a (packed) readonly object.