in reply to ENV variables....

If you'd like some bare-bones info about what Apache is making available via %ENV, here's a pretty common little cgi script: 
#!/usr/bin/perl -w
use strict;

print "Content-type: text/html\n";
print "\n";
print "<html><head>\n";
print "<title>Environment Variables</title>\n";
print "</head>\n";
print "<body>\n";
print "<table border=1>\n";
print "  <tr>\n";
print "    <td><b>Environmental Variable</b></td>\n";
print "    <td><b>Value</b></td>\n";
print "  </tr>\n";
foreach my $key (sort keys %ENV) {
   print "  <tr>\n";
   print "    <td>$key</td>\n";
   print "    <td>$ENV{$key}&nbsp;\n";
   print "  </td></tr>\n";
}
print "</table>\n";
print "</body></html>\n";

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