One used to be able to set the UDP address and port number for the UDP connection in Fldigi by navigating to the “I/O Ports” in the Configuration Menu or by configuring the ARQ/KISS/ I/O depending on the Fldigi version. In Fldigi v4.2.06 this does not appear to be possible anymore.
I read that a linux terminal command “fldigi HOSTNAME” could be used to specify the UDP address but I installed ubuntu and it does not recognize this command.

Am I missing something and if so where can I enter this UDP information?