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Re: typedef in old C

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"Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> writes:

> On 12/14/2022 12:59 PM, Ben Bacarisse wrote:
>> luser droog <luser.droog@gmail.com> writes:
>> 
>>> On Tuesday, December 13, 2022 at 7:45:34 AM UTC-6, Bart wrote:
>>>> I was looking at the 1983 C sources of PostScript (via
>>>> https://computerhistory.org/blog/postscript-a-digital-printing-press/).
>>>>
>>>> It uses typedef like this:
>>>>
>>>> typedef long int integer;
>>>> typedef unsigned integer Offset;
>>>>
>>>> That is, being able to apply 'unsigned' to a typedef-ed name, rather
>>>> than any of 'char short int long'.
>>>>
>>>> I guess this is not legal C now; I just wondered at what point it
>>>> stopped being legal, if it ever was (perhaps compilers were just more lax).
>>>
>>> Overall it seems to be "cutting edge" C for the time AFAICT.
>>> New types are used all over to convey semantic information
>>> about the variable that also makes the selection of the concrete
>>> type very DRY.
>>>
>>> Very surprising to me is the use of linked lists for the basic stacks.
>>> Since the original application in the Apple Laserwriter was very
>>> memory constrained, it's surprising that they spent the size of an
>>> extra pointer on every stack element. Even unused elements have
>>> this pointer, being linked together on their own per stack free list.
>>>
>>> OTOH this would make it easy to initialize the stacks to use whatever
>>> odd space was available after making big contiguous memory areas
>>> for other stuff. You just carve up little (next pointer, object} nodes from
>>> the desired memory and link them together into the free list.
>>
>> That's the key.  It's simple.
>> About that time I visited a research lab developing cutting edge
>> distributed systems.  Around the lab the team had pinned a huge banner
>> bearing the words "MEMORY IS CHEAP".  When I asked about this (because
>> memory was /not/ cheap or plentiful in most systems at the time) I was
>> told that, because it /will/ be cheap and plentiful, cutting edge
>> software should not waste time solving a problem that will vanish by
>> release 2.0 (or in some cases even by the first release).
>> 
>>> So maybe the memory contraints encouraged this choice even though
>>> it appears surprising that the famous "stack based language" does not
>>> in fact use "stacks" per se.
>>
>> What then, to your mind, is a stack?
>
> LIFO.

Sure, but since you didn't dispute that the linked list used by this C
code is a stack "per se", there was really no need to confirm your
position.

-- 
Ben.

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typedef in old C Bart <bc@freeuk.com> - 2022-12-13 13:45 +0000
  Re: typedef in old C Thiago Adams <thiago.adams@gmail.com> - 2022-12-13 06:42 -0800
    Re: typedef in old C Thiago Adams <thiago.adams@gmail.com> - 2022-12-13 06:46 -0800
      Re: typedef in old C Bart <bc@freeuk.com> - 2022-12-13 15:56 +0000
        Re: typedef in old C Kaz Kylheku <864-117-4973@kylheku.com> - 2022-12-13 18:07 +0000
          Re: typedef in old C Thiago Adams <thiago.adams@gmail.com> - 2022-12-13 11:11 -0800
  Re: typedef in old C Ben Bacarisse <ben.usenet@bsb.me.uk> - 2022-12-13 16:40 +0000
    Re: typedef in old C scott@slp53.sl.home (Scott Lurndal) - 2022-12-13 17:05 +0000
    Re: typedef in old C Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2022-12-13 10:27 -0800
    Re: typedef in old C Tim Rentsch <tr.17687@z991.linuxsc.com> - 2022-12-18 17:25 -0800
  Re: typedef in old C Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2022-12-13 10:30 -0800
  Re: typedef in old C luser droog <luser.droog@gmail.com> - 2022-12-14 09:42 -0800
    Re: typedef in old C Ben Bacarisse <ben.usenet@bsb.me.uk> - 2022-12-14 20:59 +0000
      Re: typedef in old C "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2022-12-14 13:44 -0800
        Re: typedef in old C Ben Bacarisse <ben.usenet@bsb.me.uk> - 2022-12-15 02:46 +0000
      Re: typedef in old C scott@slp53.sl.home (Scott Lurndal) - 2022-12-15 15:01 +0000
        Re: typedef in old C Ben Bacarisse <ben.usenet@bsb.me.uk> - 2022-12-15 17:07 +0000
      Re: typedef in old C luser droog <luser.droog@gmail.com> - 2022-12-15 18:34 -0800
        Re: typedef in old C Ben Bacarisse <ben.usenet@bsb.me.uk> - 2022-12-16 17:41 +0000
  Re: typedef in old C Bonita Montero <Bonita.Montero@gmail.com> - 2022-12-17 07:54 +0100

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