To follow up on that explanation, LWP::Simple's head() method is a very easy and economical way of testing a URL since it uses a HEAD request which does not actually send the document body around. To further facilitate the approach, you should issue a redirect to either the cam URL or the "sorry it's down" picture from the CGI depending on the test result, if it's being referred to via IMG SRC=. If the CGI's output is the cam portal's HTML page it should produce IMG SRC= tags with different URLs according to the tests' results. That way the CGI script does as little work as possible, to keep the server's load low.

Makeshifts last the longest.

In reply to Re: Testing URL existence by Aristotle
in thread [untitled node, ID 176516] by Samn

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