Megatest

(define (dbfile:simple-file-release-lock fname)
  (handle-exceptions
      exn
      #f ;; I don't really care why this failed (at least for now)
    (delete-file* fname)))

(define (dbfile:with-simple-file-lock fname proc #!key (expire-time 300))
(define (dbfile:with-simple-file-lock fname proc #!key (expire-time 300)(run-anyway #f))
  (let ((start-time (current-seconds))
        (gotlock (dbfile:simple-file-lock-and-wait fname expire-time: expire-time))
        (end-time (current-seconds))
        )
    (if gotlock
	(let ((res (proc)))
	  (dbfile:simple-file-release-lock fname)
	  res)
        (begin
          (dbfile:print-err "dbfile:with-simple-file-lock: " fname " is locked by "
			    (with-input-from-file fname
			      (lambda ()
				(dbfile:print-err (read-line)))))
          (dbfile:print-err "wait time = " (- end-time start-time))
	  (dbfile:print-err "ERROR: simple file lock could not get a lock for " fname " in " expire-time " seconds")
          #f
        )
	  (if run-anyway
	      (let ((res (proc)))
    )
  )
)

		(dbfile:simple-file-release-lock fname)
		res)
	      #f)))))

(define *get-cache-stmth-mutex* (make-mutex))

(define (db:get-cache-stmth dbdat db stmt)
  (mutex-lock! *get-cache-stmth-mutex*)
  (let* (;; (dbdat       (dbfile:get-dbdat dbstruct run-id))
	 (stmt-cache  (dbr:dbdat-stmt-cache dbdat))