pro dbclose,dummy;+; NAME:;       DBCLOSE; PURPOSE:;       procedure to close a data base file;; CALLING SEQUENCE:  ;       dbclose;; INPUTS:;       None;; OUTPUTS;       None;; SIDE EFFECTS:;       the data base files currently opened are closed;; PROCEDURE CALLS:;       DB_INFO(), HOST_TO_IEEE; HISTORY:;       version 2  D. Lindler  Oct. 1987;       For IDL version 2      August 1990;       William Thompson, GSFC/CDS (ARC), 30 May 1994;                Added support for external (IEEE) data format;       Converted to IDL V5.0   W. Landsman   September 1997;-;------------------------------------------------------------------------ On_error,2 common db_com, QDB, QITEMS, QDBREC         ;Database common - see DBOPEN if N_elements(qdb) LT 120 then return	;No db opened ndb = db_info('NUMBER')		;number of data bases opened update = db_info('UPDATE',0)		;opened for update?; If database open for update, write total number of entries in zeroeth record if update EQ 1 then begin		;update header	output = [db_info('entries',0), db_info('seqnum',0)]	if qdb[119] eq 1 then host_to_ieee, output	;External format?        qdbrec[0] = byte(output,0,8) endif for i = 0, ndb-1 do begin		;loop on units (2 per data base)        unit1 = qdb[96,i]			;unit numbers        unit2 = qdb[97,i]			;unit numbers	if unit1 gt 0 then free_lun,unit1       ;Is it opened?	if unit2 gt 0 then free_lun,unit2       ;Is it opened? endfor qdb=0					;mark as closed return                                                               end