It is enough to link an application with Terminal client libraries for the application to work correctly. The necessity for other modifications occurs only when a programmer wishes to use additional functions offered by the software, e.g. terminal transactions (which guarantee that the transaction will be completed even if there happens a disconnection with the terminal), priorities (enabling lowering the priority of an application so that more processor-overloading tasks could be run, RPC (calling out procedures performed on the terminal from an application).

More detailed clues may be found in the documentation.