My guess is that there is already a subroutine called "redirect" in one of the Perl modules that I am already using.

One way to find that out is to read the module docs. CGI makes mention of a redirect method. So you could grep through the source code, either at CGI, or at your unix command line:

grep -w redirect `perldoc -l CGI`
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Sure enough, there is a sub redirect.

Now, where does that warning message come from? A look at perldiag shows:

Subroutine %s redefined

(W redefine) You redefined a subroutine. To suppress this warning, say

   1. {
   2. no warnings 'redefine';
   3. eval "sub name { ... }";
   4. }
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Update: a closer look at CGI.pm shows that :standard exports :cgi which exports the redirect sub. An option is to only export what you need. You could change this line to not export redirect:

use CGI qw/:standard/;
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