Path: utzoo!utgpu!watserv1!watmath!att!pacbell.com!ucsd!sdcc6!hobbes!wade
From: wade@hobbes.ucsd.edu (Wade Blomgren)
Newsgroups: comp.protocols.appletalk
Subject: Re: update on Cap5 papif problem?
Summary: solution to papif exec error
Message-ID: <16309@sdcc6.ucsd.edu>
Date: 3 Feb 91 01:51:13 GMT
References: <1991Feb2.133946@riacs.edu>
Sender: news@sdcc6.ucsd.edu
Lines: 35
Nntp-Posting-Host: hobbes.ucsd.edu

In an article, bradley@riacs.edu (Brad Christofferson) writes:
> 
> Anyone seen this one before?:
> 
> psbanner: geo.arc.nasa.gov:matt  Job: hosts.lpd  Date: .....
> papif: Starting job for matt@geo.arc.nasa.gov at Wed J......
> filter setup: child exec: Permission denied
> 
> 
[copious debugging information deleted]

Yes, I've seen this exact problem before.  Basically papif is trying to
'exec' a filter with a name that is the empty string.  In (some flavors of)
Unix, the empty string is translated by the file system into the current 
working directory (".").  This empty string in this case is your "REVERSE"
filter. The papif program tries to figure out if you want (and can handle)
reversal of the pages in the output file by examining the REVERSE environment
variable (which unfortunately is in this case the empty string, not a null
string, as it is set by the shell script).  The program figures that
since the reverse variable is not NULL you must want reversal.  It tempers
this behavior somewhat by checking for the appropriate magic (!%) at the
front of the PS file and also respecting the pscomm "-r" (never reverse)
flag.  It all gets going when the papif program does an "access" call on
the (empty) psreverse (REVERSE) string, and gets success, since of course
you can access the current directory.  Later it tries to "exec" the directory,
and you see the somewhat cryptic result: "permission denied".  

The quick and dirty solution is to add the "-r" flag to the call of
$PSCOMM (really papif) in your cap version of the psif filter.  The
real solution is to fix papif to respect empty reverse strings, not
just NULL ones.  I meant to submit a bug report for papif at the time
but got distracted....sorry about that!

Wade Blomgren
wade@hobbes.ucsd.edu