There are issues other than speed of execution to consider when scanning for ports. For example intrusion detection systems (and alike) can block rapid fire requests from one host (see Whois query error: "No valid response for 4th time..." or search for other examples). Using a tool like nmap to accomplish this task could employ various techniques to negate such issues.

In reply to Re: Code for port scanner on range of IPs by marto
in thread Code for port scanner on range of IPs by ckj

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