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Xojo Plugin

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 Xojo Plugin Downloads

Xojo Plugin
Dim socket As New Chilkat.Socket

//  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.
Dim boundPort As Int32
boundPort = socket.BindAndListenPortRange(5000,5100,25)
If (boundPort < 0) Then
    System.DebugLog(socket.LastErrorText)
    Return
End If

System.DebugLog("Listening on port " + Str(boundPort))