From mboxrd@z Thu Jan 1 00:00:00 1970 From: downing.nick+tuhs@gmail.com (Nick Downing) Date: Tue, 28 Jun 2011 15:48:39 +1000 Subject: [TUHS] Ideas for a Unix paper I'm writing In-Reply-To: <20110628041302.GR39651@dereel.lemis.com> References: <20110628001140.GA23711@minnie.tuhs.org> <20110628041302.GR39651@dereel.lemis.com> Message-ID: Greg, it is very interesting what you've said about the origin of file descriptors... it might be worth looking into the history of this a bit deeper, but from what you've said the earlier systems didn't have the polymorphic file descriptors that unix has, from what I understand of your post the device nodes in the filesystem were new with unix? I totally agree that the text format and the filesystem work together to promote inter-operability and user `ownership' of their data (a recent phenomenon along the same lines is XML so we might say that unix predicts current trends by 20-25 years in this respect as well). Another really important thing to mention is the Bourne shell, it's kind of the glue that sticks it all together, and a bit of a masterpiece in itself, being fraught with compromise but having programmability and a batch capability without taking away from its main purpose of being a useable interactive shell. cheers, Nick On Tue, Jun 28, 2011 at 2:13 PM, Greg 'groggy' Lehey wrote: > On Tuesday, 28 June 2011 at 10:11:40 +1000, Warren Toomey wrote: >> >> I'm having some trouble thinking of the right way to explain what is >> an elegant design at the OS/syscall level, so any inspirations/ideas >> would be most welcome. I might highlight a couple of syscall groups: >> open/close/read/write, and fork/exec/exit/wait. > > The system call interface is one thing, but I'm not sure it's the most > important one.  Older operating systems (in my experience, IBM OS/360 > and UNIVAC Omega and OS 1100) had similar interfaces.  Omega also had > the concept of integer file descriptors (including 0, 1 and 2 > preassigned).  All of these systems had open/close/read/write, for > example. > > I came to UNIX relatively late, and my first impression wasn't > favourable.  It took me a while to realise what the real advantages > were.  For me, they're: > > - Text files.  At the time, any data of any importance was stored in >  custom-designed file formats.  That was more efficient, both in >  terms of processing time and space, but it made things difficult if >  anything went wrong. > > - The file system itself.  I think the design of the file system, >  especially the separation of names and the files themselves, but >  also special files, is one of the most far-reaching designs I've >  ever come across.  To this day, I haven't found anything that even >  comes close. > > You might also get some ideas from > http://en.wikipedia.org/wiki/Unix_philosophy > > Greg > -- > Finger grog at FreeBSD.org for PGP public key. > See complete headers for address and phone numbers. > This message is digitally signed.  See > http://www.lemis.com/grog/email/signed-mail.php for more details. > If your Microsoft MUA reports problems, please read > http://tinyurl.com/broken-mua > > _______________________________________________ > TUHS mailing list > TUHS at minnie.tuhs.org > https://minnie.tuhs.org/mailman/listinfo/tuhs > >