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The application front-end module in FORTRAN
The application back-end module in FORTRAN

Front-end

C     	  Example DTS front-end application
C
C         Perform a simple query to the remote handler HELLO
C
C     	  Language:              VAX FORTRAN
C    	  Date:                  25-NOV-1991


	program EXAMPLEFE

	implicit none

C ----------------------------- Global constants -----------------------------

	character*11	    OUR_NAME		! Our name for the remote rtn
	2		    /'TestProgram'/

	character*8	    RECEIVER_NODE	! Receiver DTS node name
	2		    /'REMOTE  '/
	character*2	    FUNCTION_CODE	! DTS function code
	2		    /'01'/		! Inquiry-type transaction
	character*8	    REMOTE_HANDLER	! Remote user handler name
	2		    /'HELLO   '/

	integer*2	    DTS_HDR_LENGTH	! DTS header length, 39 bytes
	parameter	(DTS_HDR_LENGTH = 39)	    

C ----------------- Variable definitions and field mappings ------------------
	
	character*8	    HDR_RECEIVER	! DTS header fields that must
	character*2	    HDR_FUNCTION_CODE	! be defined by the user
	character*8	    HDR_HANDLER
	character*31900	    USER_INPUT_DATA	! User data area

	character*32000     INBUFF_S		! DTS input message buffer
	logical*1	    INBUFF_B(32000)
	integer*2	    INBUFF_LEN		! Input message actual length

						! Map hdr fields and buffers
	equivalence	    (INBUFF_S,INBUFF_B)
	equivalence	    (INBUFF_S(22:29),HDR_RECEIVER)
	equivalence	    (INBUFF_S(30:31),HDR_FUNCTION_CODE)
	equivalence	    (INBUFF_S(32:39),HDR_HANDLER)
	equivalence	    (INBUFF_S(40:),USER_INPUT_DATA)

	character*2	    DTS_RETURN_CODE	! DTS return code field
	character*31900	    USER_OUTPUT_DATA	! User data area

	character*32000	    OUTBUFF_S		! DTS output message buffer
	logical*1	    OUTBUFF_B(32000)
	integer*2	    OUTBUFF_LEN		! Output message actual length

						! Map buffers and rc field
	equivalence	    (OUTBUFF_S,OUTBUFF_B)
	equivalence	    (OUTBUFF_S(1:2),DTS_RETURN_CODE)
	equivalence	    (OUTBUFF_S(3:),USER_OUTPUT_DATA)

C ------------------------------ Begin of code -------------------------------

	HDR_RECEIVER = RECEIVER_NODE		! Set receiver node name
	HDR_FUNCTION_CODE = FUNCTION_CODE	! Set DTS function code
	HDR_HANDLER = REMOTE_HANDLER		! Set remote handler name
	USER_INPUT_DATA = OUR_NAME		! Put user data to inp buff
	INBUFF_LEN =				! Input message length =
	2   DTS_HDR_LENGTH+LEN(OUR_NAME)	! DTS header + user data
						
						! Call DTS f/e service rtn
	
	call  YFIAPPC (INBUFF_B, INBUFF_LEN, OUTBUFF_B, OUTBUFF_LEN)	

	if  ( DTS_RETURN_CODE .ne. '00' ) then	! If nonzero return status,
	    type 10, OUTBUFF_S(1:OUTBUFF_LEN)	! Display error message	    
 10	    format (' Call failed : ',a)
	else					! If successful call,
	    type 20,				! Display received message
	2	USER_OUTPUT_DATA(1:OUTBUFF_LEN-2)	
 20	    format (' Message Received :',/,' ',a)
	endif

	END					! End of program

C ------------------------------ End of source -------------------------------

Back-end

C     	  Example DTS back-end application HELLO
C
C         Return a simple 'Hello' message to the calling f/e.
C
C     	  Language:              VAX FORTRAN
C    	  Date:                  25-NOV-1991



	subroutine  HELLO  ( INBUFF, INLEN, OUTBUFF, OUTLEN )

	implicit none

C ------------------ Parameters passed in the function call ------------------

	byte        INBUFF(*), OUTBUFF(*)       ! Message buffer areas
	integer*2   INLEN, OUTLEN               ! and the lengths

C ----------------------------- Global constants -----------------------------

	integer*2   DTS_HDR_LENGTH              ! DTS header length, 39 bytes
	parameter   (DTS_HDR_LENGTH = 39)	    
	integer*2   DTS_RC_LENGTH               ! DTS return code length, 2 b
	parameter   (DTS_RC_LENGTH = 2)

C ----------------- Variable definitions and field mappings ------------------
	
	byte                LOC_INBUFF(32000)   ! Local inmsg buffer
	byte                LOC_OUTBUFF(32000)  ! Local outmsg buffer

	character*31900     USER_INPUT_DATA     ! User input data area
	character*31900     USER_OUTPUT_DATA    ! User output data area

                                                ! Map hdr fields and buffers

	equivalence         (LOC_INBUFF(DTS_HDR_LENGTH+1),USER_INPUT_DATA)
	equivalence         (LOC_OUTBUFF(DTS_RC_LENGTH+1),USER_OUTPUT_DATA) 

	integer*2           LOC_LOOP            ! Local loop index

C ------------------------------ Begin of code -------------------------------

	do LOC_LOOP = 1, INLEN                  ! Copy input message to
	    LOC_INBUFF(LOC_LOOP) =              ! local formatting buffer
	2   INBUFF(LOC_LOOP)
	end do                   
	                                        ! Format response message
	USER_OUTPUT_DATA(1:) = 'Hello ' //      ! to the output buffer
	2   USER_INPUT_DATA(1:(INLEN-DTS_HDR_LENGTH)) //
	3   '. I''m your remote routine'
  
	OUTLEN = DTS_RC_LENGTH+                 ! Set output message len 
	2   (INLEN-DTS_HDR_LENGTH)+31           ! DTS ret code + user data

	do LOC_LOOP = DTS_RC_LENGTH+1, OUTLEN   ! Copy input message from
	    OUTBUFF(LOC_LOOP) =                 ! the local buffer to 
	2   LOC_OUTBUFF(LOC_LOOP)               ! actual message buffer
	end do

	return                                  ! End of subroutine task

	END                                     ! End of program

C ------------------------------ End of source -------------------------------