Re: [PLUG] Why does it produce a silent error when run from crontab?

[Ugarit Ebla <ugaritebla@gmail.com>]

cronjobs are run with a different user so there may be a permissions 
issue.  Your script doesn't cd to a directory.  You should do that.

What's root in front of the script?

Casey Bralla wrote:
> I've got a small batch program that creates a nifty near-realtime view of the 
> earth with animated cloud cover (http://www.nerdworld.org/nerdspace.html) 
> that **used** to work, but now doesn't on my Debian 4 server.
>
> I can run the program just fine from a command prompt, but it fails in a very 
> strange way when run from crontab.
>
> The program has to do some image manipulations, and to do so it 
> calls "jpegtopnm" (part of "netpbm") to convert some jpg files into pnm 
> format.
>
> Oddly, I can run the conversion script from a bash shell prompt without any 
> trouble, but the program bombs weirdly if run from crontab.   When it bombs, 
> it doesn't halt or give any kind of error message;  but jpegtopnm just 
> creates a pnm file of zero length.
>
>
> So, to summarize:
>
> When jpegtopbm runs in a script started from command prompt, it runs fine.  
> But when it runs in the same script started by crontab, it bombs silently 
> without creating the pnm image file.
>
>
>
>
>
> Here's an abbreviated version of the script file:
>
> #!/bin/bash
>
> # Create globe images with xplanet.  Create xplanet00.jpg
> /usr/bin/xplanet -body earth -num_times 1 -verbosity 1 -config 
> xplanet00.cfg -latitude 39.81 -longitude -75.90 -geometry 1003x752 -starfreq 
> 0 -projection orthographic -output xplanet00.jpg
>
> # Convert to intermediate format "pnm"
> /usr/bin/jpegtopnm -verbose xplanet00.jpg > xplanet00.pnm
> # (This is the line that does not work in batch mode)
>
>
>
>
>
>
> The crontab line looks very normal:
> 0,15,30,45 * * * *       root   /path/create.xplanet.images
>
>
>
>
>
> Anybody have any suggestions of where to explore troubleshooting this problem?
>
> All my error logs are clean.  Nothing looks amiss, except that it doesn't 
> work.  <sigh>
>
>
>   
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