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Jason Farmer - Yet Another Latex Problem

Jason Farmer - Yet Another Latex Problem

by Arnold Pizer -
Number of replies: 0
inactiveTopicYet Another Latex Problem topic started 4/15/2004; 3:20:08 PM
last post 4/27/2004; 12:15:13 PM
userJason Farmer - Yet Another Latex Problem  blueArrow
4/15/2004; 3:20:08 PM (reads: 3442, responses: 18)
Hello again all! For some reason last week, without being "touched" our TeX installation decided to take a nose dive. I have traced our problem through our error logs to the following line:
I can't find the format file `latex.fmt'!
After doing some reasearch I found that many people solved this by doing the texhash, command, but that did not solve the problem. Then I saw elsewhere to make sure that your definitions in the texmf.cnf file are correct, did that as well, and everything seems fine, as I say, it all worked before and nothing has changed. Finally I saw someone re-run the post-install scripts for teTeX, such as:
 

So I also tried these, and still nothing. Any suggestions from "the pros" out there? :)
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userJohn Jones - Re: Yet Another Latex Problem  blueArrow
4/15/2004; 4:04:56 PM (reads: 3654, responses: 
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Does latex work from the command line for you as a user?


If so, what if you login as the username the web server runs
under.  Does it work from the command line for the web server's
username?


John
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userJason Farmer - Re: Yet Another Latex Problem  blueArrow
4/15/2004; 4:21:17 PM (reads: 3655, responses: 
            0) 		
        
Apache right now is running as root. It did not used to be this way. 


And yes latex works fine from the command line. It only has problems when invoked via Webwork.
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userJohn Jones - Re: Yet Another Latex Problem  blueArrow
4/15/2004; 6:26:30 PM (reads: 3660, responses: 
            0) 		
        
It sounds like environment variables may be an issue - they certainly influence where tex will look for files.


When you say that the web server runs as root (which sounds dangerous)
but that it hasn't always been that way, did it change around the time
latex stopped working?


So, if you login as root, then latex runs fine, right?  Then,
while still logged in as root, see how environment variables are
set.  Under csh, the command printenv should do it.  Under bash, just set will list them.  To select things which might be related to TeX, I would use (under bash), set | grep -i tex .


The next step might be to see what this looks like from the web
server.  I would insert a system command to do the same, but pipe
its output to a file (e.g., system('set | grep -i tex >> /tmp/WW-envir'))
somewhere in webwork, trigger it, and then look at the result (and then
take the extra statement out).  There are probably smoother ways
to check this.


John

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userJason Farmer - Re: Yet Another Latex Problem  blueArrow
4/18/2004; 7:42:10 PM (reads: 3618, responses: 
            0) 		
        
I'm checking into this now. I do recall Apache originally running as
our webwork account, and I do not have root access, therefore it would
have to of been started by an administrator here. So I am looking into
how we may be able start Apache once again as webwork.


A question I thought of however, even though we have absolute path's
defined for all of webwork's and teTeX's settings, would it still use
environment variables for things like that?


Thanks again for the quick response.
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userJason Farmer - Re: Yet Another Latex Problem  blueArrow
4/25/2004; 12:03:49 PM (reads: 3622, responses: 
            0) 		
        
So here is what I have found out after consulting our system admin. We
are running Apache correclty (initial process is started as root to
bind to port 80, but all threads are being produced as our webwork user)


After doing some further investigation, we discovered a style file that
was causing problems (aparently missing). So we replaced that file, and
Latex will run smoothly when invoked again by the command prompt.


In the welcomeAction.pl script we added some output that output the
exact line from which Latex is invoked, and when copied to our shell,
runs perfectly. So it still seems like some configuration has changed
which prevents Latex when running within Apache to get to the same path
configurations as our shell. But our system admin consistantly says
Apache is running correctly.


Any ideas?
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userJohn Jones - Re: Yet Another Latex Problem  blueArrow
4/26/2004; 1:09:08 AM (reads: 3619, responses: 
            0) 		
        
Since these happen differently for the web server, you should try to
get a closer look at what's happening there.  In lib/Global.pm,
you can set imageDebugMode to 1.  Then have webwork generate a pdf
(or whatever is failing), and look in the error log.  Webwork may
also leave the .aux file for you.  Either of these should have
information about what is going wrong.


John


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userJason Farmer - Re: Yet Another Latex Problem  blueArrow
4/26/2004; 9:46:01 AM (reads: 3601, responses: 
            0) 		
        
I'm not sure if this problem is related, but when the logPrint()
function gets called in welcome action, it also gives an error saying
that it cannot find the logfile:

 path= /home/webwork2/webwork/system/courses/Math121-Spring04-ESorensen2/html/tmp/Temp_downloadAllSets_admin.log

No such file or directory


I think that this is just because latex never created the log file when
it was run. Basically it didn't get that far in the process.


Here is the output I can get from latex:


This is TeX, Version 3.14159 (Web2C 7.3.1)


(/home/webwork2/webwork/system/courses/Math121-Spring04-ESorensen2/html/tmp/Tem

p_downloadAllSets_admin.tex

LaTeX2e <1999/12/01> patch level 1

Babel <v3.6Z> and hyphenation patterns for american, french, german, ngerman, n

ohyphenation, loaded.



And that's all I get. Normally it ends with "(1 pages of output)" or
something like that. But nothing, no errors, no missing files. Is there
some type of debug mode in latex?
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userJason Farmer - Re: Yet Another Latex Problem  blueArrow
4/26/2004; 9:52:04 AM (reads: 3597, responses: 
            0) 		
        
I take that back. That output I found was from the command line only.
There is no output from the webwork invoked latex command (where it
does the >>error_log after the latex command). Also the "(1 pages
of output)" is from dvipng :)


I am thinking about going in and adding some other redirection or
turning on what I think is debug mode for latex WITHIN WEBWORK. In
other words adding

-kpathsea-debug=NUMBER   set path searching debugging flags according to

                         
the bits of NUMBER


to my DVI command line. Think this might give some relevant data?
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userJohn Jones - Re: Yet Another Latex Problem  blueArrow
4/26/2004; 12:43:38 PM (reads: 3576, responses: 
            0) 		
        
Latex does not usually say anything about the existence of its log
file.  Maybe it is a permissions problem and latex is really
complaining that it cannot create its log (and other output files).


Second, you might comment out lines which unlink the files
webwork/latex creates. Does latex work on the .tex file created by
webwork?  If you prevent webwork from cleaning up the files, are
there really no .aux, .dvi, and .log files?


John

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userJason Farmer - Re: Yet Another Latex Problem  blueArrow
4/26/2004; 2:26:57 PM (reads: 3609, responses: 
            0) 		
        
Well I checked all the permissions on everything once again (this was one of the first things I did) and they all look correct.


I also uncommented out the unlink line, and the files exist from
previous debugging sessions, and when I try to download them through
webwork using the "Get Hard Copy", it gives me a different error page,
without all of the *.tex output, but still the same "Software Error"
message. If I remove the files from a previous (working) session I get
the original error message including the fact that it cannot find the
log file. The only thing that sits in the directory is the *.tex file
from the process no .aux, .dvi, or .log files.


Again, I can run the command which Webwork invokes in welcomeAction.pl:


/home/webwork2/local/teTeX/bin/latex
/home/webwork2/webwork/system/courses/Math103-Spring04-ESorensen2/html/tmp/Temp_downloadAllSets_admin.tex
>>/home/webwork2/webwork/system//logs/error_log
2>>/home/webwork2/webwork/system//logs/error_log


And everything works perfectly.


I really appreciate your help John. I hope we can get this resolved. :)
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userJohn Jones - Re: Yet Another Latex Problem  blueArrow
4/26/2004; 5:36:37 PM (reads: 3594, responses: 
            0) 		
        
I am being a little slow on the uptake here.  Webwork is
complaining that it can't find the log file, which seems to be because
it was not created.


I would do all of the following:
  • clear away all old files from the html/tmp directory
  • set imageDebugMode to 1
  • comment out all lines which clean up .log files
  • chmod -R 777 /home/webwork2/webwork/system/courses/MAT103-Spring04-Esorensen2/html/tmp.
  • in the templates directory, edit texSetPreamble.tex and change batchmode to nonstopmode

Now you try to download a pdf file.  We expect
  • this will fail
  • a .tex file is created, but nothing else
  • the .tex file works when you run it through latex by hand

Then let us know what gets put into the system log file.  The change to nonstopmode should make it more informative.


John

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userJason Farmer - Re: Yet Another Latex Problem  blueArrow
4/26/2004; 7:47:00 PM (reads: 3610, responses: 
            0) 		
        
Ahh great, now we have some output. Following all the steps, yes the
creation did fail. A tex file now exists, but nothing else. And when I
manually invoke the latex command it works perfectly.


However in webwork's error log I get the following:

This is TeX, Version 3.14159 (Web2C 7.3.1)

I can't find the format file `latex.fmt'!

This is dvips(k) 5.86 Copyright 1999 Radical Eye Software (www.radicaleye.com)

/home/webwork2/local/teTeX/bin/dvips: ! Couldn't find header file tex.pro


What is strange however is that the tex log is still not being created
(even with the permissions to the directory set to 777) and latex still
works from the command line.
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userJason Farmer - Re: Yet Another Latex Problem  blueArrow
4/27/2004; 10:12:32 AM (reads: 3573, responses: 
            0) 		
        
A note on this the file exists, as it is supposed to :) Just wanted to add that.
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userJohn Jones - Re: Yet Another Latex Problem  blueArrow
4/27/2004; 11:25:15 AM (reads: 3556, responses: 
            0) 		
        
Can you login under the username the web server uses?  It sounds
like that user is the one with problems.  If you can login as that
user and latex does not work, then at least you can test things
interactively.


You could check the permissions on the latex.fmt file and the directory
it is in (.../texmf/web2c) to be sure they are world readable (and the
directory is world executable).  If you are the user who has
trouble, you could look at kpsetool -p fmt to see where it points for format files.  In lib/Global.pm, it might help to have the extended path include the directory with your latex executable.


John

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userJason Farmer - Re: Yet Another Latex Problem  blueArrow
4/27/2004; 11:43:51 AM (reads: 3545, responses: 
            0) 		
        
The user that we use for Apache is the same user (webwork2) which
created/owns all of these files. Permissions on latex.fmt are as
follows:

-rw-r--r--   1 webwork2 special   653491 Jun 20  2002 ./share/texmf/web2c/latex.fmt


The webwork2 user (which is who is supposed to be running Apache) can run latex without a hitch.


It might be a good idea to invlude the extended path of where to search
for these format files. I will try that and see if it provides any
better results.


I want to thank you again for your persistance. :)
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userArnold K. Pizer - Re: Yet Another Latex Problem  blueArrow
4/27/2004; 11:58:11 AM (reads: 3535, responses: 
            0) 		
        
Hi,


You have probably done this, but I'll mention it just to be sure
(and I'm not really that knowledgable about this, John is much more an
expert than I).


When you su to webwork2 to check how it runs latex, did you use a
switch so that you are using the full webwork2 enviorment and not your
own enviorment?


In FreeBDS I believe the command is 


su -l webwork2


 


Arnie
 
            
            
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userJason Farmer - Re: Yet Another Latex Problem  blueArrow
4/27/2004; 12:03:26 PM (reads: 3571, responses: 
            0) 		
        
Hi Arnie,


webwork2 is the user I actually log into our server with, such as 

ssh -l webwork2


Is what I normall do. I just tried specifying a format file with latex such as:

latex -fmt=latex


And it still does not work with webwork running it, but again it works
perfectly (and much faster then previously without the -fmt flag) under
the shell.


I am beginning to have a feeling that since Root is spawning the
original Apache thread, that it might be using it's environment
variables and not webwork2's. Is there somewhere within settings of
either tex or webwork where you distinctively specify a path for a
format file? Rather than just using the -fmt flag which only expects a
format name?
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userJason Farmer - Re: Yet Another Latex Problem  blueArrow
4/27/2004; 12:15:13 PM (reads: 3573, responses: 
            0) 		
        
I found this line in texmf.cnf under the web2c directory of Tex

TEXFORMATS = .;$TEXMF/web2c

Which specifies where the default format files live, however, 

we also had this line specified

TEXMF = {!!$TEXMFMAIN}


Aparently you only need the !! points when you are adding additional paths to the variable? I changed this to look like

TEXMF = {$TEXMFMAIN}

and everything appears to be working smoothly. YAY! Thank you so much
everyone for your help. I knew it had to be something simple. Thank you
again!

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