DOCTOR DARK’S DIARY – EPISODE 15
Mike York’s letter
in the last issue commented on my remarks about a couple of
aspects of Pascal, so I thought it would be a good idea to see if I could
justify what I said. First, string handling. The definition of Pascal does not
contain any reference to the string handling functions Mike York mentions. I
assume that these are a non-standard extension provided in UCSD Pascal. They
will make programming of string handling very easy for him, but will also
render his programs less portable. As I understood it, one of the aims of
Pascal was that if a program worked on one machine, it would work on another.
For this very reason, I try to use only standard Pascal when I give you my
free routines. It should then be possible to compile the code using any decent
compiler, which is surely better than if I told a Com-Pas user that they had
to get another compiler to use my stuff? Second, big numbers. I have sometimes
had cause to write programs that handle numbers with more than the 36 digits
UCSD copes with. In these circumstances, it would seem that I was not “doing
it the hard way”, so much as doing it the only way. The whole point of my
comments on the subject was to show how Pascal enables you to write programs
that work on numbers of a very large size, let us say for the sake of example
a hundred digits. I am sorry if I did not make this clear. To avoid any
further misunderstanding, I should like to point out that the foregoing
remarks are not an attack on either Mike York or the UCSD operating system. I
have read a lot about UCSD in the glossy magazines, who rave about it. So when
I saw it advertised in the said glossies, I thought, “at last, our prayers are
answered.” Then I saw the price........
If Mr R A C Treen of Burgess Hill
(see 80-BUS News Vol.2 Issue 1 page 14)
had written to me telling me how to get past the Plover room without falling down
a pit, I would have told him how to open the clam. But! I now know how to deal
with the Plover room, and am able to score 250 out of 350 on the Syrtis
Adventure. The next hundred points seem to be much more difficult to get,
however. Mr Treen, you need something like a crowbar to open the clam (which
actually isn’t a clam at all!), and one of the items of treasure which you may
not have found yet is a bit like a crowbar.......
I have found out, with the help of my brother, quite a few useful actions that
help with Level 9’s Dungeon Adventure... For instance, I know how to deal with
the giant rat, and what the octopus is for. Even the armed skeletons are no
longer a threat, but if anyone can explain why the transport system is
affected by which collar you are wearing and what the rule governing which
collar to wear is, I should be glad.
BOOK REVIEW 1 – MASTERING CP/M
This one is by Alan R Miller, who is a professor at the New Mexico Institute
of Technology, and has been using CP/M since it first emerged. It is published
by Sybex, and costs £14.50, if you get it from Maplin, which I did. And a most
unusual thing happened. Maplin were out of stock, and I had to wait a whole
fortnight! Not like them at all, so the book must be selling pretty well. It
has about 400 pages, and contains quite a lot of listings of short programs to
illustrate the points under discussion.
Any new book on CP/M’s mysteries has to be compared with the ones already
out. This is better than Rodney Zaks’ “The CP/M Handbook”, which is really for
people who are not doing any programming of their own in machine code. And it
is better than Fernandez and Ashley’s “Using CP/M”, which is for similar
people, who in addition believe that you learn more if you fill in blank lines
all through the book.
There are chapters on such useful subjects as “Adding features to BIOS”.
The sort of thing that the other two books needed, and didn’t have. The author