SET (FIRST_INPUT_ACTION)

  Specifies the program or learn sequence DECTPU should execute whenever it
  gets the first key or button event from DECwindows.

  Syntax

     SET (FIRST_INPUT_ACTION, {program_source | NONE})

  Parameters

     program_source       A string, buffer, range, learn sequence, or
                          program specifying the first input routine.  The
                          routine could be used, for example, to remove an
                          initial copyright notice when the user presses the
                          first key or mouse button.  The keyword NONE
                          deletes the current first input routine;
                          thereafter, your application is not informed when
                          DECTPU receives the first key or button event from
                          DECwindows.  Use of this built-in after the first
                          key or button event is received will cause DECTPU
                          to signal an error as it should be used only
                          before the first key or button event.

     NONE                 A keyword instructing DECTPU to delete the current
                          first input routine.