PinK method on table objects: nullwin

Table method: nullwin

Sets all fields of a window common block to null except for the ID.

 <tabobj> "nullwin" [rowid]

<tabobj> is the name of a PinK table object,
nullwin is the name of the applied method.
rowid is an ID that will be stored in the window common block. If no ID is given, the field won't be changed.