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Re: Question on ProDOS SmartPort drive remapping

glen herrmannsfeldt wrote:

Michael J. Mahon wrote:
(snip)


I'm guessing it was one of the myriad wierdnesses of JCL that created
some "utility" for a program that did nothing.



It works well for creating and deleting data sets, which the
system always does before/after running any program.


The sheer incompetence of the JCL team always amazed me--they must
have been left-over Autocoder folks (not that there was any shortage
of incompetence in a company as big as IBM).  ;-)



If you haven't read "Mythical Man Month" and do anything related to
software engineering, you should read it.  Especially the "second
system effect" which has come back again and again.  (Among others,
protected mode 80286, which we still have even though it is mostly
unused.)


Actually, it's a favorite of mine.  And I note that "the one thing we
learn from history is that no one ever learns anything from history".
;-)


The System/360 was essentially ramrodded down the throats of all the
IBM product divisions, each of which had their own architectures and
cultures--for better or worse.  It was a necessary consolidation, but
it created huge dislocations inside the company for years to come.



The idea of a unifying architecture was new at the time.
Now we have x86, must worse overall than S/360, but we have it anyway.


As one on the outside observing, I was just amazed to see 12-pass
assemblers (!) and optimizing FORTRAN compilers written in FORTRAN
coming out of the same company and running on the same machines!  ;-)



OS/360 Assembler F is, I believe, four pass.  But yes, Fortran H is
about half written in Fortran.  Most of the parts that actually
do optimization are.  The low level I/O and such are assembler.


I loved that more than half the lines of code of the optimizer were
*comments* with math proofs for the various optimizing transforms
being performed.  ;-)

Fortran G, written by Digitek, is my favorite--a 1.5-pass FORTRAN
compiler.
I don't know DOS/360 well at all. Its assembler may have a lot of passes given the smaller memory allowed. 

In the beginning (1964), it was the only assembler available to run
on our 360/50.  I wish I could say it was fun watching it spin tapes.
;-(

OK, I'll try not to extend this retro digression any further.  ;-)

-michael

NadaPong: Network game demo for Apple II computers!
Home page:  http://members.aol.com/MJMahon/

"The wastebasket is our most important design
tool--and it's seriously underused."