Typical usage sequence

1. get a file-id
   by calling load_dialog with the path to a dcl file as argument (load_dialog "c:/my_dialog.dcl") -> return value 1 If the return value is 0 or less, then the file could not be loaded.

2. get a dialog-handle
   by calling new_dialog with a dialog name and the received file-id as argument (new_dialog "my_dialog" 1)

3. set various callback functions
   by calling action_tile with a key of some tile (GUI component) and the received dialog-handle as argument

4. start a modal flow on the dialog
   by calling start_dialog (start_dialog)

5. receive and process user input
   through the callback functions and using various DCL API calls to alter the state of the dialog

6. terminate the dialog
   by calling done_dialog with the dialog-handle as argument The default callback automatically calls done_dialog when cancel or ok is clicked.

7. unload the dcl file
   by calling unload_dialog with the file-id as argument (unload_dialog 1)