I see from code you've posted in another node that your operating in a cgi environment. So the simplest way would be to display the version number in the browser.

You should also display the perl version number $], and the contents of both @INC and %INC.

The server will not let me get the variables:

#!/usr/local/bin/perl

print "Content-type: text/html\n\n";
print "<code>\n";

foreach $key (sort keys(%ENV)) {
  print "$key = $ENV{$key}<p>";
}
[download]

I get an internal server error message

I know nothing about cgi servers. but it seems very clear to me that your setup is completely broken. If you do not have direct access to it, then you will have to contact the appropriate support people to fix it.

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