Megatest

		    "cp "backupfname" "fname)))
    (dbfile:print-err "WARNING: attempting recovery of file "fname" by running commands:\n"
		      "  "cmd)
    (system cmd)))

;; opens and returns handle and nothing else
;;
;; NOTE: this is already protected by mutex *no-sync-db-mutex*
;;
(define (dbfile:raw-open-no-sync-db dbpath)
  (if (not (file-exists? dbpath))
      (create-directory dbpath #t))
  (debug:print-info 0 *default-log-port* "Opening "dbpath"/no-sync.db")
  (let* ((dbname    (conc dbpath "/no-sync.db"))
	 (db-exists (file-exists? dbname))
	 (init-proc (lambda (db)
		      (sqlite3:with-transaction
		       db
		       (lambda ()
			 ;; I have been having trouble with init of no-sync.db so
			 ;; doing the init in a transaction every time (no gating
		      (if (not db-exists)
			 ;; on file existance.
			  (for-each
			   (lambda (stmt)
			     (sqlite3:execute db stmt))
			   (list
			    "CREATE TABLE IF NOT EXISTS no_sync_metadat
                                (var TEXT,
                                 val TEXT,
                                   CONSTRAINT no_sync_metadat_constraint UNIQUE (var));"
			    "CREATE TABLE IF NOT EXISTS no_sync_locks 
                                (key TEXT,
                                 val TEXT,
                                   CONSTRAINT no_sync_metadat_constraint UNIQUE (var));")))))
                                   CONSTRAINT no_sync_metadat_constraint UNIQUE (key));"))))))
	 (on-tmp      (equal? (car (string-split dbpath "/")) "tmp"))
	 (db        (if on-tmp
			(dbfile:cautious-open-database dbname init-proc 0 "WAL")
			(dbfile:cautious-open-database dbname init-proc 0 #f)
			;; (sqlite3:open-database dbname)
			)))
    (if on-tmp	      ;; done in cautious-open-database
	(begin
	  (sqlite3:execute db "PRAGMA synchronous = 0;")
	  (sqlite3:set-busy-handler! db (sqlite3:make-busy-timeout 136000))))
    db))

(define (dbfile:with-no-sync-db dbpath proc)
  (mutex-lock! *no-sync-db-mutex*)
  (let* ((already-open *no-sync-db*)
  (let* ((db  (dbfile:raw-open-no-sync-db dbpath))
	 (db  (or already-open (dbfile:raw-open-no-sync-db dbpath)))
	 (res (proc db)))
    (if (not already-open)
    (sqlite3:finalize! db)
	(sqlite3:finalize! db))
    (mutex-unlock! *no-sync-db-mutex*)
    res))

(define *no-sync-db-mutex* (make-mutex))

(define (dbfile:open-no-sync-db dbpath)
  (mutex-lock! *no-sync-db-mutex*)
  (let* ((res (if *no-sync-db*
		  *no-sync-db*
		  (let* ((db (dbfile:raw-open-no-sync-db dbpath)))
		    (set! *no-sync-db* db)
		    db))))