• The open() method.
  • Should handle all initialization.
    • This includes getting any command-line parameters or switches.
    • Do not initialize in a constructor.
      • This will cause problems if the primitive needs to be restarted. (More on this later.)
      • NeXtMidas uses reflection to call primitives. If the constructor takes in any arguments, NeXtMidas won't know how to call it.
      • Primitives should not even have a constructor declared.
  • Should open any files used.
    • If a pipe is opened in process(), there may be data loss.
  • Should return one of the following:

    NORMAL	Normal operation, ready for process().
    FINISH	Nothing to process, skip to close(). (This is rarely used.)

  • Example of using FINISH: A primitive that takes in a list of files to process may return FINISH if no files are given.