! *** PREDECLARED TYPES
     
      %IF %DECLARED ( %BASIC$QUADWORD_DECLARED ) = 0 %THEN
         RECORD BASIC$QUADWORD
            LONG FILL ( 2 )
         END RECORD
         %LET %BASIC$QUADWORD_DECLARED = 1
      %END %IF
     
      %IF %DECLARED ( %BASIC$OCTAWORD_DECLARED ) = 0 %THEN
         RECORD BASIC$OCTAWORD
            LONG FILL ( 4 )
         END RECORD
         %LET %BASIC$OCTAWORD_DECLARED = 1
      %END %IF
     
      %IF %DECLARED ( %BASIC$HFLOAT_AXP_DECLARED ) = 0 %THEN
         RECORD BASIC$HFLOAT_AXP
            LONG FILL ( 4 )
         END RECORD
         %LET %BASIC$HFLOAT_AXP_DECLARED = 1
      %END %IF
     
      %IF %DECLARED ( %BASIC$F_FLOATING_COMPLEX_DECL ) = 0 %THEN
         RECORD BASIC$F_FLOATING_COMPLEX
            SINGLE REAL_PART
            SINGLE IMAGINARY_PART
         END RECORD
         %LET %BASIC$F_FLOATING_COMPLEX_DECL = 1
      %END %IF
     
      %IF %DECLARED ( %BASIC$D_FLOATING_COMPLEX_DECL ) = 0 %THEN
         RECORD BASIC$D_FLOATING_COMPLEX
            DOUBLE REAL_PART
            DOUBLE IMAGINARY_PART
         END RECORD
         %LET %BASIC$D_FLOATING_COMPLEX_DECL = 1
      %END %IF
     
      %IF %DECLARED ( %BASIC$G_FLOATING_COMPLEX_DECL ) = 0 %THEN
         RECORD BASIC$G_FLOATING_COMPLEX
            GFLOAT REAL_PART
            GFLOAT IMAGINARY_PART
         END RECORD
         %LET %BASIC$G_FLOATING_COMPLEX_DECL = 1
      %END %IF
     
      %IF %DECLARED ( %BASIC$H_FLOAT_AXP_CMPLX_DCL ) = 0 %THEN
         RECORD BASIC$H_FLOATING_COMPLEX_AXP
            BASIC$HFLOAT_AXP REAL_PART
            BASIC$HFLOAT_AXP IMAGINARY_PART
         END RECORD
         %LET %BASIC$H_FLOAT_AXP_CMPLX_DCL = 1
      %END %IF
    
    
    ! 
    !         RMS Context XAB associated with the FAB
    !                 $xabcxfdef
    ! 
      DECLARE LONG CONSTANT XAB$C_CXF = 32  !  XABCXF id code
      DECLARE LONG CONSTANT XAB$M_CXFRST = x'00000001'
      DECLARE LONG CONSTANT XAB$S_XABCXFDEF = 60
      record XABCXFDEF
         BYTE XABCXFDEF$$_FILL_1            !  COD - xab id code
         BYTE XABCXFDEF$$_FILL_2            !  BLN - block length
         WORD XABCXFDEF$$_FILL_3            !  (spare)
         LONG XABCXFDEF$$_FILL_4            !  NXT - xab chain link
    !  UP TILL NOW COMMON AMONG ALL XABS
    ! 
    !         Following in common with the CXR block, too.
    !         Do not rearrange without changing both.
    ! 
         LONG XAB$L_CXFSTS                  !  Status of the last file operation.
         LONG XAB$L_CXFSTV                  !  Status Value of the last file operation.
    ! 
    !  Top four bits of the options longword are reserved for the XABCXR.  These
    !  bits describe the version of the key buffer.
    ! 
         group XAB$R_CXFCOP_OVERLAY
            variant
               case
                  LONG XAB$L_CXFCOP         !  Context Options.
               case
                  group XAB$R_CXFCOP_BITS
                      !  Restore file state - use context blk as input.
                     BYTE CXFRST_bits   ! COMMENT ADDED BY SDL - CXFRST_bits contains bits CXFRST through FILL_15_
                  end group XAB$R_CXFCOP_BITS
            end variant
         end group XAB$R_CXFCOP_OVERLAY
         LONG XAB$L_CXFBKP                  !  Bookkeeping bits
         WORD XAB$W_CXFIFI                  !  Internal File Identifier
         BYTE XAB$B_CXFVER                  !  prologue version num
         BYTE XABCXFDEF$$_FILL_5            !  spare to longword align commonality
         LONG XABCXFDEF$$_FILL_6            !  spare
    ! 
    !         Up Till now in common with XABCXR, too.
    ! 
    !         The following fields correspond to those in the FAB or IFB
    !         They should not be rearranged as their order is assumed for
    !         purposes of moving large chunks of data rather than a byte
    !         or word at a time.  Note: ASSUME is used in the actual code
    ! 
         WORD XAB$W_CXFDEQ                  !  Default extention quantity
         BYTE XAB$B_CXFFAC                  !  File access
         BYTE XAB$B_CXFSHR                  !  File Sharing
         WORD XAB$W_CXFRTE                  !  (Not used)
         BYTE XABCXFDEF$$_FILL_7            !  spare
         BYTE XAB$B_CXFORG                  !  file organization
         WORD XAB$W_CXFGBC                  !  global buffer count
         BYTE XAB$B_CXFRTV                  !  retrieval window
         BYTE XABCXFDEF$$_FILL_8
         LONG XABCXFDEF$$_FILL_9 ( 1 to 4 )    !  spares
      end record XABCXFDEF
    
    !  basealign on aggregate XABCXFDEF operates after aggregate end
      DECLARE LONG CONSTANT XAB$K_CXFLEN = 60  !  length of xab type CXF
      DECLARE LONG CONSTANT XAB$C_CXFLEN = 60  !  length of xab type CXF