VMS Help LBR Routines, LBR$FLUSH, Condition Values Returned  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    LBR$_NORMAL        Operation completed successfully.
    LBR$_BADPARAM      Error. A value passed to the LBR$FLUSH routine
                       was either out of range or an illegal value.
    LBR$_WRITERR       Error. An error occurred during the writing of
                       the cached update blocks to the library file.