Re: Hyper C and Davex

[zcaa1122@rpool6.rus.uni-stuttgart.de (Wulf Hofbauer)]

In article <2hpu64$kbj@terminator.rs.itd.umich.edu>,
Jeff W. Schroeder <teke@milton.ccs.itd.umich.edu> wrote:

>The reason I am here is I want to learn to program in C.
>Problem is I only have an apple IIe.  Could someone please
>point me in the direction of a compiler and some literature
>that can get me started?  I have a copy of hyper C, but thats
>it.  I don't really know where to begin.  I was told that the
>flavor of C supported by hyper C is something like K&R or KNR?
>C?  Couldn't find any books describing it at the book store.

Newer C books normally describe ANSI C which has enough differences
to K&R C to make them useless in learning the language unless you
have enough experience to work out the differences yourself.
K&R stands for "Kernighan & Ritchie", the authors of the book
"Programming in C" which describes what is known as K&R C (newer
editions of this book describe ANSI C, again).

If you can get an old copy of K&R, I would recommend it. Be warned however
that it is NOT a tutorial and you'll need some programming experience in
another structured language, e.g. in Pascal. If you know Assembly Language,
you may also get along with it. If you know Basic only, I doubt you will
be able to understand this book - there are many ideas and concepts in
programming that a typical Basic implementation never heard of, so you
won't know them, either.

Alas, I don't know any C tutorial that I could recommend - most books just
don't describe the C language but rather a specific environment of a C
implementation and don't even state this difference clearly.

Btw, HyperC is very similar, but not identical to K&R C. Floating point
is not supported in a K&R conformant way, and the preprocessor directives
are different. HyperC has however some nice extensions to K&R.

>At work we will soon be implementing a geographic information
>system.  It will most likely run on either a 486 or Pentium
>PC or a unix based mini.  I would like to get a jump on learning
>C at home and fiddle with the apple.

HyperC is great for programming the Apple //, but unless you've a lot
of programming experience, it won't help you much for another C system.
To write any useful program in C, you'll need to use externally supplied
libraries. ANSI C provides standardized libraries, otherwise, they libraries
are VERY system-dependent. This isn't a real obstacle in learning C, but it
may cause a lot of confusion to the novice.

>I currently utilize Davex as a prodos unix-like shell.  Is davex
>written in C or assembly?

I don't use it, but I'm sure it's written in assembly.

>I read somewhere that there is a unix os called opix available
>for the IIe.  I haven't been able to find it on any of the FTP
>sites.

This is not nearly Unix. Opix is a runtime environment for HyperC that
adds some, but only some, features of Unix to ProDOS. Opix is a replacement
for OPSYS, the original HyperC runtime module. Opix requires that you have
a 65C02 processor.
I've been thinking of making Opix more Unix-like (ie. make it a multitasking
system), but on a standard Apple // system this is fruitless (not enough
memory for multitasking to be useful, too slow).

Opix 1.01 should be available at calvin.sfasu.edu, grind.isca.uiowa.edu,
cco.caltech.edu and most other major sites. A new version is on the way.
-- 
 ______________________________________________________
|                                                      |
| Wulf Hofbauer | zcaa1122@rpool1.rus.uni-stuttgart.de |
|                                                      |