clsnam

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

    The address of a character-string descriptor pointing to the
    name of a protected object class. This argument is optional and
    defaults to FILE.

 objnam

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

    The address of a character-string descriptor pointing to the
    name of a protected object. This argument is optional. If it is
    omitted, the access name table returned is that used for objects
    of the class specified by the clsnam argument.

 accnam

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

    The address of a longword into which this routine writes the
    address of the access name table.