Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 beta 4/12/84; site rlgvax.UUCP Path: utzoo!watmath!clyde!burl!ulysses!mhuxl!houxm!houxz!vax135!cornell!uw-beaver!tektronix!hplabs!hao!seismo!rlgvax!guy From: guy@rlgvax.UUCP (Guy Harris) Newsgroups: net.unix Subject: Re: Re: marketing unix Message-ID: <2097@rlgvax.UUCP> Date: Wed, 11-Jul-84 22:12:53 EDT Article-I.D.: rlgvax.2097 Posted: Wed Jul 11 22:12:53 1984 Date-Received: Sat, 14-Jul-84 01:29:16 EDT References: <1475@pegasus.UUCP> Organization: CCI Office Systems Group, Reston, VA Lines: 23 > TO Erik E Fair, > I have not personally used BSD unix so I can't make any speed claims, The file system is definitely faster. > BUT how upward compatable is 4.1 to 4.2?? 4.2BSD has a "compatibility mode" option where any VAX-11 binary built for 4.1BSD will execute under 4.2BSD, unless it tries to read directories (the directory format changed). > All AT&T BTL Unix's are upward compatable. If one takes that statement literally, so that "AT&T BTL UNIXes" isn't the same as "BTL UNIXes" (i.e., only referring to UNIXes offered *after* BTL changed it's name to AT&T BL), it's not a big statement; the only UNIX AT&T BTL ever offered was System V (can an S5R2 linker handle S5R1 object modules)? If one takes "AT&T BTL" to refer to Bell Labs generically, it's false as V6 wasn't upward compatible with V7, and (more importantly) V7 wasn't upward compatible with System III. Guy Harris {seismo,ihnp4,allegra}!rlgvax!guy