uib_va

    OpenVMS usage: address
    type:          quadword (unsigned)
    access:        read only
    mechanism:     by reference
    Address of a quadword that contains the virtual address of an
    unwind information block (UIB).

 gp_value

    OpenVMS usage: address
    type:          quadword (unsigned)
    access:        read only
    mechanism:     by reference
    Address of a quadword that contains the GP value that must be
    added to the UIB condition handler value. Must be specified if
    handler_fv is specified.

 uw_desc_va

    OpenVMS usage: address
    type:          quadword (unsigned)
    access:        write
    mechanism:     by reference
    Address of a quadword to store the virtual address of the unwind
    descriptor area. If none is present, then zero is returned. This
    is an optional argument.

 un_desc_len

    OpenVMS usage: address
    type:          quadword (unsigned)
    access:        write
    mechanism:     by reference
    Address of a quadword to store the length (in bytes) of the
    unwind descriptor area. If none are present, then zero is
    returned. This is an optional argument.

 handler_fv

    OpenVMS usage: address
    type:          quadword (unsigned)
    access:        write
    mechanism:     by reference
    Address of a quadword to store the function value of the
    condition handler. If none is present, then zero is returned.
    This is an optional argument.

 ossd_va

    OpenVMS usage: address
    type:          quadword (unsigned)
    access:        write
    mechanism:     by reference
    Address of a quadword to store the address of the operating
    system-specific data area. If none is present, then zero is
    returned. This is an optional argument.

 lsda_va

    OpenVMS usage: address
    type:          quadword (unsigned)
    access:        write
    mechanism:     by reference
    Address of a quadword to store the address of the language-
    specific data area (LSDA). If none is present, then zero is
    returned. This is an optional argument.