If your question is targeted to CGI-programming you might find the ubiquitous env.pl script useful: 
#!/bin/perl
print "Content-type: text/html\n\n";
print "<HTML>\n";
print "<TITLE>Server-provided Environment variables</TITLE>";
print "<BODY>\n";
print "<TABLE>\n";
print "<TR><TD colspan=2 align=center>Environment Variables</TD></TR>\
+n";
foreach my $x (keys %ENV) {
  print "<TR><TD>$x</TD><TD>$ENV{$x}</TD></TR>\n";
}
print "</TABLE></BODY></HTML>\n";

[download]
Put it in your cgi-bin (if it's not already there, I think it comes default with apache). Be sure it is executable by the user the webserver runs as. Otherwise google for an active env.pl on somebody elses webserver.

In reply to Re: list of all the $env variables by eXile
in thread list of all the $env variables by Anonymous Monk

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