Library /sys$common/syshlp/dbg$help.hlb DEBUG, EXAMINE, Qualifiers, /VARIANT  *Conan The Librarian (sorry for the slow response - running on an old VAX)

       /VARIANT=variant-selector address-expression
       /VARIANT=(variant-selector,...) address-expression

    Enables the debugger to display the correct item when it
    encounters an anonymous variant.

    In a C program, a union contains members, only one of which is
    valid at any one time. When displaying a union, the debugger does
    not know which member is currently valid.

    In a PASCAL program, a record with a variant part contains
    variants, only one of which is valid at any one time. When
    displaying a record with an anonymous variant part, the debugger
    does not know which variant is currently valid, and displays all
    variants by default.

    You can use the /VARIANT qualifier of the EXAMINE command to
    select which member of a union (C) or anonymous variant (PASCAL)
    to display.