Store the time you made the latest retrieval. Issue a HEAD request with the 'If-Modified-Since' header set. Don't not do a retrieval if the response is a '304 Not Modified'.

Of course, a webserver may not honor the 'If-Modified-Since' header, or send a 200 anyway. There's no guaranteed way of finding out whether a page has changed without retrieving it.

In reply to Re: www::mechanize check if webpage has updated by JavaFan
in thread www::mechanize check if webpage has updated by Anonymous Monk

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