Megatest

      #f
      (handle-exceptions
	  exn
	(begin
	  (print "Attempt to safely close sqlite3 db failed. Trying again. exn=" exn)
	  (thread-sleep! 3)
	  (sqlite3:interrupt! db)
	  (db:safely-close-sqlite3-db db try-num: (- try-num 1)))
	  (db:safely-close-sqlite3-db db stmtcache try-num: (- try-num 1)))
	(if (sqlite3:database? db)
	    (let* ((stmts (hash-table-ref/default stmt-cache db #f)))
	      (if stmts (map sqlite3:finalize! (hash-table-values stmts)))
	      (sqlite3:finalize! db)
	      #t)
	    #f))))

	;; (db:sync-touched dbstruct 0 force-sync: #t) ;; NO. Do not do this here. Instead we rely on a server to be started when there are writes, even if the server itself is not going to be used as a server.
        (let ((tdbs       (map db:dbdat-get-db 
			       (stack->list (dbr:dbstruct-dbstack dbstruct))))
              (mdb        (db:dbdat-get-db (dbr:dbstruct-mtdb   dbstruct)))
              (rdb        (db:dbdat-get-db (dbr:dbstruct-refndb dbstruct)))
	      (stmt-cache (dbr:dbstruct-stmt-cache dbstruct)))
          (map (lambda (db)
		 (db:safely-close-sqlite3-db stmt-cache db))
		 (db:safely-close-sqlite3-db db stmt-cache))
	       tdbs)
          (db:safely-close-sqlite3-db stmt-cache mdb)     ;; (if (sqlite3:database? mdb) (sqlite3:finalize! mdb))
          (db:safely-close-sqlite3-db stmt-cache rdb))))) ;; (if (sqlite3:database? rdb) (sqlite3:finalize! rdb))))))
          (db:safely-close-sqlite3-db mdb stmt-cache)     ;; (if (sqlite3:database? mdb) (sqlite3:finalize! mdb))
          (db:safely-close-sqlite3-db rdb stmt-cache))))) ;; (if (sqlite3:database? rdb) (sqlite3:finalize! rdb))))))

;;   (let ((locdbs (dbr:dbstruct-locdbs dbstruct)))
;;     (if (hash-table? locdbs)
;; 	(for-each (lambda (run-id)
;; 		    (db:close-run-db dbstruct run-id))
;; 		  (hash-table-keys locdbs)))))

			  (string->number res)
			  #f)))
          (if newres
              newres
              res))
        res)))

(define (db:no-sync-close-db db)
  (db:safely-close-sqlite3-db db))
(define (db:no-sync-close-db db stmtcache)
  (db:safely-close-sqlite3-db db stmtcache))

;; transaction protected lock aquisition
;; either:
;;    fails    returns  (#f . lock-creation-time)
;;    succeeds (returns (#t . lock-creation-time)
;; use (db:no-sync-del! db keyname) to release the lock
;;