FUNCTION IGETTDI ( IFLAG )

C$$$  SUBPROGRAM DOCUMENTATION BLOCK
C
C SUBPROGRAM:    IGETTDI
C   PRGMMR: ATOR            ORG: NP12       DATE: 2009-03-23
C
C ABSTRACT: DEPENDING ON THE VALUE OF THE INPUT FLAG, THIS FUNCTION
C   EITHER RETURNS THE NEXT USABLE SCRATCH TABLE D INDEX FOR THE
C   CURRENT MASTER TABLE OR ELSE RESETS THE INDEX BACK TO ITS
C   MINIMUM VALUE.
C
C PROGRAM HISTORY LOG:
C 2009-03-23  J. ATOR    -- ORIGINAL AUTHOR
C
C USAGE:    CALL IGETTDI ( IFLAG )
C   INPUT ARGUMENT LIST:
C     IFLAG    - INTEGER: FLAG: IF SET TO 0, THEN THE FUNCTION WILL
C                RESET THE SCRATCH TABLE D INDEX BACK TO ITS MINIMUM
C                VALUE; OTHERWISE, IT WILL RETURN THE NEXT USABLE
C                SCRATCH TABLE D INDEX FOR THE CURRENT MASTER TABLE
C
C   OUTPUT ARGUMENT LIST:
C     IGETTDI  - INTEGER: NEXT USABLE SCRATCH TABLE D INDEX FOR THE
C                CURRENT MASTER TABLE
C                  -1 = FUNCTION WAS CALLED WITH IFLAG=0
C
C REMARKS:
C    THIS ROUTINE CALLS:        BORT
C    THIS ROUTINE IS CALLED BY: READMT   READS3   STSEQ
C                               Not normally called by application
C                               programs.
C
C ATTRIBUTES:
C   LANGUAGE: FORTRAN 77
C   MACHINE:  PORTABLE TO ALL PLATFORMS
C
C$$$

	PARAMETER ( IDXMIN = 62976 )
C*			   = IFXY('354000')

	PARAMETER ( IDXMAX = 63231 )
C*			   = IFXY('354255')

	CHARACTER*128	BORT_STR

	SAVE IDX

C-----------------------------------------------------------------------
C-----------------------------------------------------------------------

	IF ( IFLAG .EQ. 0 ) THEN

C*	  Initialize the index to one less than the actual minimum
C*	  value.  That way, the next normal call will return the
C*	  minimum value.

	  IDX = IDXMIN - 1
	  IGETTDI = -1
	ELSE
	  IDX = IDX + 1
	  IF ( IDX .GT. IDXMAX ) GOTO 900
	  IGETTDI = IDX
	ENDIF

	RETURN
 900	CALL BORT('BUFRLIB: IGETTDI - IDXMAX OVERFLOW')
	END