Set nonblocking mode and use select or just use IO::Socket, where the work is already done for you. Internally it's using nonblocking mode. The Timeout value is used for other operations, so you may want to reset it once the connection is up. 
my $socket=IO::Socket::INET->new(PeerAddr => '127.0.0.1',
                  PeerPort => 80,
                  Proto => 'tcp',
                  Timeout => 5);

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In reply to Re: Socket timeouts without ALARM by kschwab
in thread Socket timeouts without ALARM by ton

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