Displays a dialog box and begins accepting user input
(start_dialog)
You must first initialize the dialog box by a previous new_dialog call. The dialog box remains active until an action expression or callback function calls done_dialog. Usually done_dialog is associated with the tile whose key is "accept" (typically the OK button) and the tile whose key is "cancel" (typically the Cancel button).
The start_dialog function has no arguments.
Return Values
The start_dialog function returns the optional status passed to done_dialog. The default value is 1 if the user presses OK, 0 if the user presses Cancel, or -1 if all dialog boxes are terminated with term_dialog. If done_dialog is passed an integer status greater than 1, start_dialog returns this value, whose meaning is determined by the application.
