Tcl

Bind and Listen on an Available Port in a Range

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.

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Tcl


load ./chilkat.dll

set socket [new_CkSocket]

#  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.
set boundPort [CkSocket_BindAndListenPortRange $socket 5000 5100 25]
if {$boundPort < 0} then {
    puts [CkSocket_lastErrorText $socket]
    delete_CkSocket $socket
    exit
}

puts "Listening on port $boundPort"

delete_CkSocket $socket