getsubres uses XmGetSecondaryResourceData to fetch the widget
resources that XtGetResourceList won't see.
You can specify which widget resources to display on the command
line by using the syntax "getsubres CLASS_NAME" with one of those names:
Object, RectObj, Widget, Core, Composite, Constraint,
Primitive, ScrollBar, ArrowB, List, Separator, TextF,
Label, DrawnB, PushB, ToggleB, CascadeB, Text,
Gadget, ArrowBG, SeparatorG, LabelG, PushBG, ToggleBG,
CascadeBG, Manager, BulletinB, DrawingA, Frame, MainW,
Form, RowCol, ScrolledW, PanedW, SelectionB, FileSB,
MessageB, Scale, Command, Display, Screen, DragContext,
DragIcon, DropSiteMgr, DropTransfer, DragOverS,
Shell, OverrideShell, WMShell, MenuShell, VendorS,
ToplevelShell, ApplicationShell, TransientShell,
DialogShell, Container, IconGadget, Notebook, ComboBox,
SpinBox, SimpleSpinBox. (default is Widget)
Or you can use "getsubres All".