Path: utzoo!utgpu!news-server.csri.toronto.edu!bonnie.concordia.ca!uunet!auspex!guy From: guy@auspex.auspex.com (Guy Harris) Newsgroups: comp.os.misc Subject: Re: What constitutes a good OS? (re: file systems) Message-ID: <5393@auspex.auspex.com> Date: 20 Jan 91 21:50:57 GMT References: <1211@cvbnetPrime.COM> <1997@necisa.ho.necisa.oz.au> Organization: Auspex Systems, Santa Clara Lines: 22 >I've always thought that the I/O system should be re-written so that >everything is a stream. Including files you access randomly? >That way you could get arbitrary functionality by pushing a line >discipline (or stack of them) onto _any_ file. After moving the streams mechanism out of the kernel? Or do I have to add all this functionality as kernel-mode streams modules? In some ways this seems equivalent to an Apollo-like object-oriented file system, or implementable atop that (in fact, Apollo implemented S5-style streams, or STREAMS if you will :-), atop their object-oriented file system; see "A Dynamically Extensible Streams Implementation" in the proceedings of the Summer 1987 USENIX). >Plan 9 also has an append file type. All writes go at the end of the >file. I.e., it's more or less a file that, under UNIX, would always have O_APPEND turned on whenever it's opened for writing?