UNIX for Dummies Questions & Answers

Hi all
Recently i had finished a perl script. When i run manually, the script work fine.
But when i wanted to put the script in cron, it didn't get the same output as it run manually. I felt that it only execute the script until certain line then it stop as i see most of the related files didn't update after the script run by cron. Below is the cron i put

0,30 * * * * perl /home01/user/cheah/trigger_resend/complete.pl >/dev/null 2>&1


Did anyone can help on this?
Thanks very much...........

- Did u try to use absolute path pf perl binary like, "/usr/bin/perl".
- Remember all your standard output/error you are redirecting to null.
by the wat what output should you expect ? where do you expect it?

- nilesh

i havent try the absolute path.
What do you mean by "Remember all your standard output/error you are redirecting to null"
The output i meant is that i expected the script will generate 5 files after it being execute. But when using cron, it only generate one of the file, feel like the script processing half way

Did you find anything in cron log ?
I assume your script has executable permissions. I tried following simple code in my host,

Code:

#!/bin/bash
for i in 1 2 3 4 5
do
	touch file_$i
	echo "File generated : file_$i"
done

with these crontab settings,

This is working for me....

- nilesh

When you execute from your account there is an ENVIRONMENT. When you execute from cron there is no built-in environment and if you need anything like paths, etc. you have to specify it in your script, e.g.

$ENV{PATH} = "/x/y/z"; or what ever...

my $list_var;
open(HNDL, ">/some/simple/file.txt");
foreach $list_var ( sort keys %ENV )
{
print HNDL "$list_var -- $ENV{$list_var}\n";
}
close HNDL;

Try that from both your command line and from cron and see what the difference is in your environments. When you run from cron you might be missing something you will need to specify...

take out the stdout a<nd stderr rediction, wait until it runs, and read the mail for the user in which you are executing that
(you need a mta)

Hi Airwalker83,
If you haven't tried, you may put this as the first line of your perl script:
#!/usr/bin/env perl

and edit your crontab as:
0,30 * * * * /home01/user/cheah/trigger_resend/complete.pl >/dev/null 2>&1

assuming your script is executable.
----------------------
If this doesn't solve your problem, you may try to put the following line as the first line of your script :
. /home/(username)/.bash_profile
to set the necessary environment in the script because of the reasons "quine" mentioned and leaving the crontab as your original post.