Megatest

    (dbr:dbstruct-dbtmpname-set! dbstruct tmpdb)
    (dbr:dbstruct-dbfname-set!   dbstruct dbfname)
    (dbr:dbstruct-sync-proc-set! dbstruct
				 (lambda (last-update)
				   (if *sync-in-progress*
				       (debug:print 3 *default-log-port* "WARNING: overlapping calls to sync to disk")
				       (let* ((sync-cmd (conc "megatest -db2db -from "tmpdb" -to "dbfullname"&"))
					      (synclock-file (conc dbfullname".sync-lock")))
					      (synclock-file     (conc dbfullname".sync-lock"))
					 ;; (mutex-lock! *db-with-db-mutex*) ;; this mutex is used when overloaded or during a query that modifies the db
					 ;; (if (eq? (dbfile:cache-method) 'cachedb)
					      (synclock-mod-time (if (file-exists? synclock-file)
					 ;;     (dbmod:sync-gasket tables last-update cachedb db
					 ;; 			dbfullname syncdir keys)
					 (if (< (file-modification-time tmpdb)
						(file-modification-time dbfullname))
					     (debug:print 0 *default-log-port* "Skipping sync, "tmpdb" older than "dbfullname)
								     (handle-exceptions
									 exn
								       #f
								       (file-modification-time synclock-file))
								     #f))
					      (thethread         (lambda ()
					     (if (file-exists? synclock-file)
						 (debug:print 0 *default-log-port* "Skipping sync, lockfile "synclock-file" found.")
						 (thread-start! (make-thread
								 (lambda ()
								   (set! *sync-in-progress* #t)
								   (debug:print-info "Running "sync-cmd)
								   (system sync-cmd)
								   (thread-start!
								    (make-thread
								     (lambda ()
								       (set! *sync-in-progress* #t)
								       (debug:print-info "Running "sync-cmd)
								       (system sync-cmd)
								   ;; (mutex-unlock! *db-with-db-mutex*)
								   ;; (thread-sleep! 0.5) ;; ensure at least 1/2 second down time between sync calls
								   (set! *sync-in-progress* #f))))))
					 ))))
								       (set! *sync-in-progress* #f)))))))
					 (if (< (file-modification-time tmpdb)
						(file-modification-time dbfullname))
					     (debug:print 0 *default-log-port* "Skipping sync, "tmpdb" older than "dbfullname)
					     (if synclock-mod-time
						 (if (< (- (current-seconds) synclock-mod-time) 20) ;; something wrong with sync, remove file
						     (begin
						       (handle-exceptions
							   exn
							 #f
							 (delete-file synclock-file))
						       (thethread))
						     (debug:print 0 *default-log-port* "Skipping sync, lockfile "synclock-file" found."))
						 (thethread)))))))
    ;; (dbmod:sync-tables tables #f db cachedb)
    ;; (if db
    (dbmod:sync-gasket tables #f cachedb db dbfullname 'fromdest keys) ;; ) ;; load into cachedb
    (dbr:dbstruct-last-update-set! dbstruct (current-seconds)) ;; should this be offset back in time by one second?
    dbstruct))

;;    (if (eq? syncdir 'todisk) ;; sync to disk normally, sync from in dashboard