! ----- VALID_USER.FUN -----
	!
	! ----- FUNCTION THAT RETURNS FALSE IF THE PASSED ARGUMENT -----
	! ----- IS A VALID USERNAME IDENTIFIER -----
	!
	! ----- Last Change 07/02/93 by Brian Lomasky -----
	!
	FUNCTION WORD VALID_USER(STRING THE_USER, WORD I_O_CHNL,	&
		WORD SKIP_ERROR_MESSAGES)

		%INCLUDE "NUSER.INC"

		EXTERNAL WORD FUNCTION SEARCH_RIGHTSLIST(WORD, WORD,	&
			WORD)			! READ MATCHING RIGHTSLIST REC

		VALID_USER = TRUE		! ASSUME ERROR STATUS
		IF DEBUG_MODE THEN
			PRINT "DEBUG>Call VALID_USER for " +		&
				TRM$(THE_USER) + " on chnl " + NUM1$(I_O_CHNL)
		END IF
		! ----- ERROR IF ARGUMENT IS TOO LONG -----
		IF LEN(TRM$(THE_USER)) < 1% OR LEN(TRM$(THE_USER)) > 12% THEN
			PRINT
			PRINT "Error - Username argument is" +		&
				" out of range: " + TRM$(THE_USER) + BEL
			PRINT
			EXIT FUNCTION
		END IF

		! ----- SEARCH DESIRED RIGHTSLIST.DAT FILE BY ITS -----
		! ----- ALTERNATE KEY #2 TO CHECK FOR A VALID USERNAME -----
		KGB_NAME = THE_USER		! STORE USERNAME TO SEARCH FOR
		IF NOT SEARCH_RIGHTSLIST(I_O_CHNL, 2%, FALSE) THEN
			EXIT FUNCTION IF SKIP_ERROR_MESSAGES
			! ----- PRINT ERROR IF IDENTIFIER IS NOT A -----
			! ----- USERNAME -----
			PRINT
			PRINT "Error - " + TRM$(THE_USER) +		&
				" is not an existing username identifier" + BEL
			PRINT
			EXIT FUNCTION
		END IF

		IF KGB_IDENTIFIER < 0% THEN	! ERROR IF NOT IN UIC FORMAT
			! ----- PRINT ERROR IF IDENTIFIER IS NOT A -----
			! ----- USERNAME -----
			PRINT
			PRINT "Error - " + TRM$(THE_USER) +		&
				" is not a username - it's an identifier" + BEL
			PRINT
			EXIT FUNCTION
		END IF

		! ----- SAVE THIS USER'S UIC -----
		SEARCH_HOLDER(0%) = KGB_IDENTIFIER
		VALID_USER = FALSE		! RETURN SUCCESS STATUS
	END FUNCTION