Pascal not considered harmful - was Re: Rich kids are into COBOL

Johnny Billquist bqt at update.uu.se
Fri Feb 20 19:36:16 CST 2015


On 2015-02-21 02:11, Rich Alderson wrote:
> From: Johnny Billquist
> Sent: Friday, February 20, 2015 4:51 PM
>
>> On 2015-02-21 01:44, ben wrote:
>
>>> How do handle byte operations in C like *x++ on a PDP 10?
>
>> Do you need information on how byte operations and byte pointers work on
>> a PDP-10?
>
>> KCC, which is the one C compiler for the PDP-10 I sortof know something
>> about, use 9 bit chars, and of course you then get four bytes to a word.
>> Not sure what in your question is hard to see how it is done.
>
> Are you even certain that it is a byte operation???  All I see is an increment
> of an object in memory pointed to by the variable "x".

Good point. I just assumed that x was a char pointer. But actually, 
unless I'm confused, it's a dereference of x (which is some kind of 
pointer), followed by an increment of that pointer. But I could be 
remembering wrong in which order these operations bind.

> Now, had we been told what the declaration of "x" is, the question would be
> more meaningful, but if it's something less than word sized, then the byte
> manipulation instructions would work just fine.
>
> I don't see a problem, and think that this is a pretty weak straw man.

Agree. Not sure what ben was trying to make of this. No matter which way 
to read things, there are no special problems on a PDP-10.

	Johnny

-- 
Johnny Billquist                  || "I'm on a bus
                                   ||  on a psychedelic trip
email: bqt at softjar.se             ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol


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