Dbm: module{	PATH: con "/dis/lib/dbm.dis"; 	Datum:	type array of byte; 	Dbf: adt {		create:	fn(file: string, perm: int): ref Dbf;		open:	fn(file: string, flags: int): ref Dbf; 		fetch:	fn(db: self ref Dbf, key: Datum): Datum;		delete:	fn(db: self ref Dbf, key: Datum): int;		store:	fn(db: self ref Dbf, key: Datum, dat: Datum, replace: int): int;		firstkey:	fn(db: self ref Dbf): Datum;		nextkey:	fn(db: self ref Dbf, key: Datum): Datum; 		flush:	fn(db: self ref Dbf); 		isrdonly:	fn(db: self ref Dbf): int; 		dirf:	ref Sys->FD;	# directory		pagf:	ref Sys->FD;	# page		flags:	int;		maxbno:	int;	# last `bno' in page file		bitno:	int;		hmask:	int;		blkno:	int;	# current page to read/write		pagbno:	int;	# current page in pagbuf		pagbuf:	array of byte;	# [PBLKSIZ]		dirbno:	int;	# current block in dirbuf		dirbuf:	array of byte;	# [DBLKSIZ]	}; 	init:	fn();};