Why does cron kill this script??

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

When run from the command line or the web, the following code works just fine but when run from cron I get this error... Can't call method "get_tag" without a package or object reference at line 122. Any suggestions to correct this are most appreciated!

$p = HTML::TokeParser->new(shift||"$file");

  while (my $token = $p->get_tag("a")) {
         my $url = $token->[1]{href} || "-";
         my $text = $p->get_trimmed_text("/a");
         push @array, $url; 
         }
[download]

Comment on Why does cron kill this script?? Download Code

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Re: Why does cron kill this script?? by chipmunk (Parson) on Jan 07, 2002 at 02:56 UTC
You haven't verified that HTML::TokeParser->new() succeeds, so you go on to call $p->get_tag() even though $p is empty. The call to HTML::TokeParser->new() is probably failing because the script cannot find the specified file, or the script doesn't have the appropriate permissions to open it.	[reply]
Re: Why does cron kill this script?? by kschwab (Vicar) on Jan 07, 2002 at 05:25 UTC
This sort of thing usually happens when the script writer makes too many assumptions about cron. The general environment that a script gets from cron isn't the same as the one you get when you log in. Things to check: Does the script depend on being in a certain directory to run ? ( chdir() there explicitly in the script) Does the script depend on certain environment variables ? cron doesn't read your ".profile" file. The PATH environment variable is a common problem.	[reply]
Re: Why does cron kill this script?? by rbc (Curate) on Jan 07, 2002 at 05:42 UTC
I think the error you are getting is the result of ... use strict; somewhere in your script or libs included by your script. So you need to 'maybe' say ... my $p = HTML::... Why this error manifest itself when executed from cron is probably do to the environment cron runs in vs. your command line env. ... as others have pointed out -- Its like a dog that can sing and dance. It's remarkable because it can do it. Not that it can do it well.	[reply]
(jeffa) 2Re: Why does cron kill this script?? by jeffa (Bishop) on Jan 07, 2002 at 06:51 UTC
Actually, it is the result of a non-existing file: `use strict; use HTML::TokeParser; my $p = HTML::TokeParser->new(shift); my $token = $p->get_tag("a"); [jeffa@trinity perl]$ ./bar.pl asdfsdaf Can't call method "get_tag" on an undefined value at ./bar.pl line 7.` [download] Not declaring $p with my yields: `Global symbol "$p" requires explicit package name ...` [download] So i'd put my money on the bet that strict is not being used or $p was declared earlier. More likely getting home paths mixed up. jeffa L-LL-L--L-LL-L--L-LL-L-- -R--R-RR-R--R-RR-R--R-RR F--F--F--F--F--F--F--F-- (the triplet paradiddle)	[reply] [d/l] [select]