From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-0.4 required=5.0 tests=AC_FROM_MANY_DOTS,BAYES_00 autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,bc1361a952ec75ca X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2001-09-04 11:55:02 PST Path: archiver1.google.com!newsfeed.google.com!sn-xit-02!supernews.com!newsfeed.direct.ca!look.ca!newsfeed.icl.net!opentransit.net!newsfeeds.belnet.be!news.belnet.be!psinet-eu-nl!psiuk-p4!uknet!psiuk-n!news.pace.co.uk!nh.pace.co.uk!not-for-mail From: "Marin David Condic" Newsgroups: comp.lang.ada Subject: Re: Ada OS talk (was: Progress on AdaOS) Date: Tue, 4 Sep 2001 14:34:43 -0400 Organization: Posted on a server owned by Pace Micro Technology plc Message-ID: <9n36s5$jqh$1@nh.pace.co.uk> References: <9n2jcd$b50$1@nh.pace.co.uk> <3B950BAD.B23ECB43@san.rr.com> NNTP-Posting-Host: dhcp-200-133.miami.pace.co.uk X-Trace: nh.pace.co.uk 999628485 20305 136.170.200.133 (4 Sep 2001 18:34:45 GMT) X-Complaints-To: newsmaster@news.cam.pace.co.uk NNTP-Posting-Date: 4 Sep 2001 18:34:45 GMT X-Priority: 3 X-MSMail-Priority: Normal X-Newsreader: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Xref: archiver1.google.com comp.lang.ada:12714 Date: 2001-09-04T18:34:45+00:00 List-Id: Well, I don't know what you want to call an "Operating System" but there are plenty of real time OS's that never deal with the concept of a "File" because the hardware has no use for it. An OS can have a means of bootstrapping itself into some flavor of memory and start executing without there being a "File System" in any conventional sense. Hence I believe that its possible to deal with lower-level execution issues & get something capable of running a program and save any file system issues for a later date. (Oh, you'd probably have to dummy some things up since typically a program has got to reside *somewhere* - but if the OS has some rudimentary monitor built into it to enable program loading from some collection of sources, you could build something that worked, without having to deal with a file system.) I understand the notion of having no visible file system in the traditional sense. "Disk" is just seen as a kind of extension to "Memory". I have no objection to that sort of design - except possibly that it makes you incompatible to some extent with the rest of the universe and may have some limitations. (How are you going to get at Unix or Windows files on a network if there is no visible file system - or some extension thereof? Ada has facilities for handling "files" so there ought to be some kind of support for that. Does it need to be "traditional"? Not necessarily - but it ought to allow for the fact that you'll want to look at stuff that isn't built under your own home-grown system.) I kind of like a generalization that says "all that exists is 'storage' so don't distinguish between an array in memory and a file on disk". However, any practical OS is going to have to deal with the need to get real specific about devices & hardware at points in time. For embedded things, this is obvious: "I need this particular EEPROM or that specific I/O port..." But even in general purpose computers, programmers will find a need to insist that data reside in specific physical devices. As long as you can get there from here, I'm happy. One of the better ideas I've heard was to base any file system on URLs so that the interface to the software is the same no matter what kind of data or where it resides. That works nicely in conjunction with XML as the means for handling any GUI development. However, I'm still convinced that those sorts of issues can and should be stalled off until some small level of working OS is actually built and running. MDC -- Marin David Condic Senior Software Engineer Pace Micro Technology Americas www.pacemicro.com Enabling the digital revolution e-Mail: marin.condic@pacemicro.com Web: http://www.mcondic.com/ "Darren New" wrote in message news:3B950BAD.B23ECB43@san.rr.com... > > Any OS can treat the file system as a whole separate issue. > > Not really. My point was that it's possible to create an OS where the > concept of "file system" doesn't even exist. I'm not sure what your > "kernel" is going to do other than process scheduling and I/O. What did > you have in mind? > > Take a look, for example, at the EROS operating system. It's a bit > radical, but there aren't really "files" as such in it, in the sense > that the entire disk is one giant swap file and files are simply > variables held by processes. You do IPC to a process that has access to > the data you want in order to get it. The data isn't just "there" > without a process to access it for you. > > -- > Darren New > San Diego, CA, USA (PST). Cryptokeys on demand.