XINU was: Unix and C

[Eric Berggren]

rmartin at clear.com (Bob Martin) writes:

>In <4458 at mint39.UUCP> gunda at motcid.UUCP (Indira Gunda) writes:

>>richb at railnet.UUCP (Richard Banks) writes:

>>>How can Unix be written in C ? I thought all OS`s had to be written
>>>in assembly language, else they'd have the same interrupts as the
>>>OS you booted your complier language under to write the program ?

>>Yes ... Why and how can UNIX be written in C?  I'd also like to know.

>There is an excellent book on the subject.  Although I can't think
>of the complete title and author, it is a very common book and I am
>sure another poster will be able to identify it better than I.

>The title of the book is something like "The XINU operating system."

>This book contains a complete miniature operating system written 
>almost entirely in C.  It is well written and the source can be
>obtained magnetically if desired.  Certainly this book is worth
>exploring if you are interested in the contstruction of operating 
>systems.

  The name of the book is _Operating System Design: The XINU Approach_,
by Douglas Comer, and it is quite good. I picked it up only a couple of
months ago and I just started typing in the code. There's a "standard"
edition (written for a PDP11, meant to be ported), and a PC edition, of
which I'm working on. It's isn't the best OS, and, of course, wasn't
meant to be, but the code is written openly and the reader is encouraged
to make improvements. 
  If qunda at motcid is really interested in this type of stuff, MINIX might
be interesting, but for around $150.


==============================================================================

     "Round and round the while() loop goes;
           Whether it stops," Turing says, "nobody knows."
==============================================================================

     "Round and round the while() loop goes;
           Whether it stops," Turing says, "nobody knows."