Perl & cron job environmental variables

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

I have to use Perl in a "cron" job.
However, my environmental variables seem not to export to Perl (but they do seem to export to csh.) Running the following "cron" job:

/usr/bin/csh -c printenv

Produces the correct set of environmental variables.

However, the Perl script "cron" job:

/home/username/bin/perlprintenv.pl

where the code is simply:

#!/usr/local/perl -w

foreach $c (keys %ENV) {
        print "$c \t".$ENV{$c}."\n";
        }
[download]

produces a much shorter list of variables and a shorter path. I am running Solaris.
What is the recommended "fix" for this problem?

Is there any easy way to force cron to export all variables?

Comment on Perl & cron job environmental variables Download Code

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Re: Perl & cron job environmental variables by Fletch (Bishop) on Jul 02, 2007 at 20:26 UTC
Jobs run from `cron` do not run under your login environment so yes, you'll seem to be missing a bunch of environment variables. Either explicitly set them in the crontab (which may depend on your particular OS' cron implementation), write a wrapper script which (say) sources your "normal" shell configuration file (e.g. `~/.cshrc` or `~/.bashrc` or what not) and then that is what runs your Perl, or set them explicitly with `$ENV{FOO}="/bar/baz/quux";` statements in your code. And to fend off the likely next posting: don't try just doing `system( "source ~/.cshrc" )` in your code; it won't work.	[reply] [d/l] [select]
Re: Perl & cron job environmental variables by toolic (Bishop) on Jul 02, 2007 at 20:49 UTC
As Fletch mentioned, you can create a csh wrapper script around your Perl script: `#!/bin/csh /home/username/bin/perlprintenv.pl` [download] then use a crontab entry like this: `* * * * * /home/username/bin/wrapper.csh` [download] This worked for me on my solaris machine.	[reply] [d/l] [select]
Re: Perl & cron job environmental variables by djp (Hermit) on Jul 03, 2007 at 03:33 UTC
You might like an explanation of what's happening here. By default, csh reads your .cshrc file, unless the -f switch is specified. That's why your environment is populated for the csh script but not for the Perl script. It's good practice in csh scripts to specify '#!/bin/csh -f' on the shebang line, to prevent reading .cshrc. It's better practice to avoid csh scripts altogether, see http://www.faqs.org/faqs/unix-faq/shell/csh-whynot for details.	[reply]
Re: Perl & cron job environmental variables by dorko (Prior) on Jul 02, 2007 at 20:29 UTC
What happens when you use csh to run your Perl program? I have no idea if this will work: `/usr/bin/csh /usr/local/perl /home/username/bin/perlprintenv.pl` [download] (Other answers will be better, and this might not even work... It just feels quick and dirty.) Cheers, Brent -- Yeah, I'm a Delt.	[reply] [d/l]
Re: Perl & cron job environmental variables by Anonymous Monk on Jul 03, 2007 at 01:29 UTC
Hi, We created a file with all the environment we needed, then called the cron job : + + + + + /usr/bin/csh source env.file; perljob.pl which worked just fine. We even put Sybase env variables in the file which meant we didn't need to put them in a BEGIN block. J.C.	[reply]
Re: Perl & cron job environmental variables by Anonymous Monk on Jul 02, 2007 at 20:20 UTC
Update: I am using Perl 5.6.1	[reply]


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