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Ruby

Bind and Listen on an Available Port in a Range

See more Socket/SSL/TLS Examples

Demonstrates Socket.BindAndListenPortRange, which searches an inclusive port range for an available TCP port, binds it, and begins listening. It returns the selected port, or -1 on failure.

Background. This is useful when any of several ports is acceptable and the application needs to discover which one was bound.

Chilkat Ruby Downloads

Ruby
require 'chilkat'

socket = Chilkat::CkSocket.new()

#  Search the inclusive port range for an available TCP port, bind it, and begin listening.  The
#  method returns the selected port, or -1 when no port can be bound.
boundPort = socket.BindAndListenPortRange(5000,5100,25)
if (boundPort < 0)
    print socket.lastErrorText() + "\n";
    exit
end

print "Listening on port " + boundPort.to_s() + "\n";