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=-1.9 required=5.0 tests=BAYES_00 autolearn=ham autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,3cd3b8571c28b75f X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2003-08-26 11:34:30 PST Path: archiver1.google.com!news1.google.com!newsfeed.stanford.edu!news-spur1.maxwell.syr.edu!news.maxwell.syr.edu!fu-berlin.de!uni-berlin.de!hse-mtl-ppp75387.qc.sympatico.CA!not-for-mail From: Christopher Browne Newsgroups: comp.lang.ada Subject: Re: A Customer's Request For Open Source Software Date: 26 Aug 2003 18:34:28 GMT Organization: cbbrowne Computing Inc Message-ID: References: <3F44BC65.4020203@noplace.com> <20030822005323.2ff66948.david@realityrift.com> <20030822020403.625ffbf5.david@realityrift.com> <3F4657AD.1040908@attbi.com> <3F4828D9.8050700@attbi.com> <3F48D263.8060004@noplace.com> <3F48E863.3080806@attbi.com> <3F4A02FB.5050504@noplace.com> NNTP-Posting-Host: hse-mtl-ppp75387.qc.sympatico.ca (64.229.212.148) X-Trace: news.uni-berlin.de 1061922868 9216475 64.229.212.148 (16 [125932]) X-Draft-From: ("nntp+chvatal:comp.lang.ada" 21765) X-message-flag: Outlook is rather hackable, isn't it? X-Home-Page: http://www.cbbrowne.com/info/ X-Affero: http://svcs.affero.net/rm.php?r=cbbrowne Xref: archiver1.google.com comp.lang.ada:41866 Date: 2003-08-26T18:34:28+00:00 List-Id: In an attempt to throw the authorities off his trail, Marin David Condic transmitted: > If you started with a "Single User" system, then all operations can > take place in RAM - of whatever sort. This would be no different > than editing a document with a word processor that is not > journaling. If you take a power hit, you lose your work to that > point in time. You get done posting transactions or generating > reports - you "Exit - Save" and your work is written to a > database. (The simplest form would be a stream file where you do a > 'Write for your data structure.) > > From there, you can consider if you want to make this a multi-user > system. There is a strong tendancy for systems designed in this manner to NOT play well when they move over to allow concurrency. I think I can characterize it all in one word: "Windows." In spite of there being Windows NT around, which _was_ designed as a multiuser multitasking system, since so much of the software had its genesis with companies that assumed ONE user running ONE program on some variation of Windows 95, which was a thin layering of GUI atop MS-DOS, what we see now is that "Windows applications" are basically designed for a single user OS, and most don't play well if you have multipel instances of things around. Concurrency is _hard_, and if you don't design it in at the beginning, it is quite likely that by the time you get around to it, the system design will probably preclude having it _really_ work... -- output = ("cbbrowne" "@" "acm.org") http://www.ntlug.org/~cbbrowne/languages.html "It's not about 'Where do you want to go today?'"; "It's more like, 'Where am I allowed to go today?'"