library_index

    OpenVMS usage:longword_unsigned
    type:         longword (unsigned)
    access:       read only
    mechanism:    by reference
    Library control index returned by the LBR$INI_CONTROL library
    routine. The library_index argument is the address of the
    longword that contains the index.

 txtrfa

    OpenVMS usage:vector_longword_unsigned
    type:         longword (unsigned)
    access:       read only
    mechanism:    by reference
    The module's record file address (RFA) of the library module
    header. The txtrfa argument is the address of the 2-longword
    array that specifies the RFA of the module header.