XtCreatePopupShell() - create a popup shell
Widget XtCreatePopupShell (String name, WidgetClass widget_class,
Widget parent, ArgList args,
Cardinal num_args)
The XtCreatePopupShell(3) function ensures that the specified class is a subclass of Shell and, rather than using insert_child to attach the widget to the parent's children list, attaches the shell to the parent's pop-ups list directly.
A spring-loaded pop-up invoked from a translation table already must exist at the time that the translation is invoked, so the translation manager can find the shell by name. Pop-ups invoked in other ways can be created ``on-the-fly'' when the pop-up actually is needed. This delayed creation of the shell is particularly useful when you pop up an unspecified number of pop-ups. You can look to see if an appropriate unused shell (that is, not currently popped up) exists and create a new shell if needed.
XtPopup()
X Toolkit Intrinsics - C Language Interface
Xlib - C Language X Interface