! ----- VALID_FILE.FUN -----
	!
	! ----- FUNCTION TO SEE IF FILE EXISTS -----
	!
	! ---------- PASSED: ----------
	! -----		FILE_SPEC = File spec to search for
	! ---------- RETURNED: ----------
	! -----		VALID_FILE = TRUE if the passed filespec exists, else
	! -----			     FALSE
	!
	! ----- Last Change 07/06/93 by Brian Lomasky -----
	!
	FUNCTION WORD VALID_FILE(STRING FILE_SPEC)

		%INCLUDE "NUSER.INC"

	%INCLUDE "$FABDEF" %FROM %LIBRARY "SYS$LIBRARY:BASIC$STARLET.TLB"
	%INCLUDE "$NAMDEF" %FROM %LIBRARY "SYS$LIBRARY:BASIC$STARLET.TLB"
	%INCLUDE "$RMSDEF" %FROM %LIBRARY "SYS$LIBRARY:BASIC$STARLET.TLB"

		DECLARE FABDEF FAB		! DEFINE THE FAB BLOCK
		DECLARE LONG LOCAL_STATUS	! SYSTEM SERVICE EXIT STATUS
		DECLARE NAMDEF NAM		! DEFINE THE NAM BLOCK

		EXTERNAL LONG FUNCTION SYS$PARSE! $PARSE SYSTEM SERVICE
		EXTERNAL LONG FUNCTION SYS$SEARCH ! $SEARCH SYSTEM SERVICE

		! ----- FIXED-LENGTH STRINGS PASSED TO/FROM RMS -----
		MAP (FPARSE)	STRING SEARCH_SPEC = 255%,		&
				STRING EXPANDED_SPEC = 255%,		&
				STRING RESULT_SPEC = 255%

		SEARCH_SPEC = FILE_SPEC		! STORE PASSED FILE SPEC
		EXPANDED_SPEC = ""		! CLEAR EXPANDED FILE SPEC
		RESULT_SPEC = ""		! CLEAR RESULTING FILE SPEC

		! ----- SET UP THE FAB BLOCK -----
		FAB::FAB$B_BID = FAB$C_BID	! FAB BLOCK IDENTIFIER
		FAB::FAB$B_BLN = FAB$C_BLN	! FAB BLOCK LENGTH
		! ----- LOCATION OF PASSED FILE SPEC -----
		FAB::FAB$L_FNA = LOC(SEARCH_SPEC)
		FAB::FAB$B_FNS = LEN(FILE_SPEC)	! LENGTH OF PASSED FILESPEC
		FAB::FAB$L_NAM = LOC(NAM)	! LOCATION OF NAM BLOCK

		! ----- SET UP THE NAM BLOCK -----
		NAM::NAM$B_BID = NAM$C_BID	! NAM BLOCK IDENTIFIER
		NAM::NAM$B_BLN = NAM$C_BLN	! NAM BLOCK LENGTH
		IF NAM$C_MAXRSS > 127% THEN
			! ----- SIZE OF RESULTING SPEC -----
			NAM::NAM$B_RSS = NAM$C_MAXRSS - 256%
		ELSE
			! ----- SIZE OF RESULTING SPEC -----
			NAM::NAM$B_RSS = NAM$C_MAXRSS
		END IF
		! ----- LOCATION OF RESULTING SPEC -----
		NAM::NAM$L_RSA = LOC(RESULT_SPEC)
		IF NAM$C_MAXRSS > 127% THEN
			! ----- SIZE OF EXPANDED SPEC -----
			NAM::NAM$B_ESS = NAM$C_MAXRSS - 256%
		ELSE
			! ----- SIZE OF EXPANDED SPEC -----
			NAM::NAM$B_ESS = NAM$C_MAXRSS
		END IF
		! ----- LOCATION OF EXPANDED SPEC -----
		NAM::NAM$L_ESA = LOC(EXPANDED_SPEC)

		LOCAL_STATUS = SYS$PARSE(FAB)	! GET INITIAL FILE INFORMATION
		IF LOCAL_STATUS = RMS$_DNF THEN	! IF DIRECTORY NOT FOUND:
			VALID_FILE = FALSE	! RETURN "NON-EXIST" STATUS
			EXIT FUNCTION
		END IF
		IF (LOCAL_STATUS AND 1%) = 0% THEN
			PRINT "Error for SYS$PARSE: " + NUM1$(LOCAL_STATUS)
			CALL LIB$STOP(LOCAL_STATUS BY VALUE)
		END IF

		! ----- GET THE REST OF THE FILE INFORMATION -----
		LOCAL_STATUS = SYS$SEARCH(FAB)
		IF (LOCAL_STATUS AND 1%) = 0% THEN
			VALID_FILE = FALSE	! RETURN "NON-EXIST" STATUS
		ELSE
			VALID_FILE = TRUE	! RETURN "FILE EXISTS" STATUS
		END IF
	END FUNCTION