you could check the HTTP referer field

But be careful. The HTTP spec makes the referer header optional, and (in violation of the spec) a number of proxy servers munge the referer to either a URL advertising the proxy, or to a string of Xs. You could lock users out by accident.

In reply to Re^2: OT- HTML Page and Frame Question by dorward
in thread OT- HTML Page and Frame Question by Anonymous Monk

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


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