I can access most of the environment variables, but for some reason I cannot access the HTTP_REFERER environment variable. Is it possible that some of these environment variables are locked out by the server? Here is the very simple test script: 
#!/usr/bin/perl
print ("Content-type: text/html\n\n");
print "<HTML><HEAD><TITLE>Environment Variables</TITLE></HEAD><BODY>";
print "<p><b>$ENV{'HTTP_USER_AGENT'} $ENV{'HTTP_REFERER'}</b></p>";
print "</BODY></HTML>";
open(FILE,">>testdata");
print FILE "\nHere";
close (FILE);

[download]
The HTTP_USER_AGENT is displayed but not the REFERER. Thanks in advance.

In reply to HTTP_REFERER by Anonymous Monk

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