!*** MODULE $XABDEF ***
!DEC$ OPTIONS/ALIGN=(RECORDS=PACKED,COMMONS=PACKED)/NOWARN
 ! 
 !          definitions for all xabs
 !                 $xabdef
 ! 
 !   the first four fields are shared in common between all xabs
 !   and hence are defined only once
 !   (the only exception is that the spare word may be used by some xabs)
 ! 
	STRUCTURE /XABDEF/
	    BYTE      XAB$B_COD			 !  xab id code
	    BYTE      XAB$B_BLN			 !  block length
	    INTEGER*2 %FILL				 !  (spare)
	    INTEGER*4 XAB$L_NXT			 !  xab chain link
	    INTEGER*2 XAB$W_RVN
	    INTEGER*2 %FILL
	    UNION
	        MAP
	        INTEGER*4 XAB$Q_RDT(2)
	        END MAP
	        MAP
	            INTEGER*4 XAB$L_RDT0
	            INTEGER*4 XAB$L_RDT4
 ! COMMON AMONG DAT AND RDT XABS
	        END MAP
	    END UNION
	END STRUCTURE	! XABDEF
	STRUCTURE /XABDEF1/
	    BYTE      %FILL(1:8)
	    BYTE      %FILL				 ! THESE FIELDS WILL BE DEFINED LATER
	    BYTE      %FILL
	    INTEGER*2 %FILL
	    INTEGER*4 %FILL
	    INTEGER*4 %FILL
	    INTEGER*2 %FILL
	    BYTE      XAB$B_BKZ			 ! COMMON TO FHC AND ALQ XABS
	END STRUCTURE	! XABDEF1
	PARAMETER XAB$C_CXT_VER1 = '00000001'X	 !  RMS Context Extraction version 1
!DEC$ END OPTIONS