merlyn pointed out years ago that the quickest way to do the actual fetch is to connect a socket on port 80, print a simple "GET / HTTP/1.0\n\n" to the socket, then just read the first x bytes (enough to check for a 200 OK) and disconnect. This saves the data/time overhead of fetching the full page, and also prevents issues with sites that don't give HEAD :-)

In reply to Re^2: Question: Fast way to validate 600K websites by tachyon-II
in thread Question: Fast way to validate 600K websites by lihao

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