This question would probably be more apropriate to a discussion forum related to your webserver. However, in the spirit of Perlmonks I offer you a short perl/CGI script that will show you all the environmental variables that are available so you can see if you can find one that suits your needs. 
#!/usr/bin/perl -w
use strict;
use CGI qw(:standard);
print header,
  start_html(-title => 'ENV vars', -bgcolor => 'white');
foreach (sort keys %ENV){
  print "<b>$_</b> -> \"$ENV{$_}\"\n<br>\n";
}
print   end_html;

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In reply to Re: The Environment variable for URL... by lhoward
in thread The Environment variable for URL... by SYbeginner

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