display-id

    OpenVMS usage:identifier
    type:         longword (unsigned)
    access:       write only
    mechanism:    by reference

    Identifier of the new virtual display to be loaded with the
    saved virtual display. The display-id argument is the address
    of an unsigned longword into which is written the new display
    identifier.

 filespec

    OpenVMS usage:char_string
    type:         character string
    access:       read only
    mechanism:    by descriptor

    String containing the file specification of the file in which the
    specified virtual display is saved. The filespec argument is a
    character string containing the file specification.

    If filespec is omitted, SMG$LOAD_VIRTUAL_DISPLAY searches for the
    default file specification SMGDISPLY.DAT.