(Tcl) Bind and Listen on a Randomly Selected Unused Port

Demonstrates how to bind and listen on a randomly selected unused port.

Note:The ListenPort property used in this example is available starting in Chilkat v9.5.0.59.

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load ./chilkat.dll

# This example requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

set listenSocket [new_CkSocket]

# Pass a value of 0 for the port number to randomly select
# an unused port.
# (The 2nd argument allows for a backlog of 25 pending connection requests when accepting connections.)
set success [CkSocket_BindAndListen $listenSocket 5555 25]
if {$success != 1} then {
    puts [CkSocket_lastErrorText $listenSocket]
    delete_CkSocket $listenSocket
    exit
}

# Find out what port was chosen.
# Note: The ListenPort propety was added in Chilkat v9.5.0.59
set listenPort [CkSocket_get_ListenPort $listenSocket]
puts "Chosen listen port = $listenPort"

delete_CkSocket $listenSocket