IO::Socket::INET. Here's a command line one for you, s/"/'/ and s/'/"/ on *nix as this is Win32 quoting ;-) 
perl -MIO::Socket::INET -le "do{$s=IO::Socket::INET->new(PeerAddr=>'12
+7.0.0.1',PeerPort=>$_,Timeout=>1);print $s? $_.' OPEN' : $_.' CLOSED'
+}for ARGV[0]..$ARGV[1]" 1 1024

[download]

You should also check out the Perl Power Tools Project which has ported many of the popular *nix command line tools to Perl.

cheers

tachyon

In reply to Re: System utilities with Perl by tachyon
in thread System utilities with Perl by Anonymous Monk

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