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Re: Memorry error?

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Keith Thompson <kst-u@mib.org> wrote:

> raltbos@xs4all.nl (Richard Bos) writes:
> > Keith Thompson <kst-u@mib.org> wrote:
> [...]
> >> I suspect that the same header that declared GetString has:
> >> 
> >>     typedef char *string;
> >> 
> >> If so, that's unfortunate, since it encourages the misconception that
> >> strings are "really" pointers.  (A string is by definition "a contiguous
> >> sequence of characters terminated by and including the first null
> >> character"; a char* may or may not be a pointer to a string.)
> >
> > It's equally unfortunate because it pretends that strings are _not_
> > "really" pointers, but some weird abstract type that might somehow
> > change from a character sequence accessed by a char *.
> 
> I don't follow you.  You seem to be implying that strings are "really
> pointers", which they most certainly are not.

No, the string itself is not a pointer. But the object you use to access
that string really _is_ a pointer. My point was that hiding char *
behind a "string" typedef hides _both_ of these facts, that a string is
a set of characters which isn't a pointer, and also that a string is
accessed through a bog-standard char *. 
For a thorough understanding of how C treats strings and char pointers
(and pointers in general, really), it is important to realise that this
works just fine without needing to hide it behind a typedef. So the
typedef is even more unfortunate than you already pointed out.

Richard

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Memorry error? Alla _ <modelling.data@gmail.com> - 2015-11-07 05:18 -0800
  Re: Memorry error? Alla _ <modelling.data@gmail.com> - 2015-11-07 05:19 -0800
  Re: Memorry error? Alla _ <modelling.data@gmail.com> - 2015-11-07 05:27 -0800
  Re: Memorry error? Alla _ <modelling.data@gmail.com> - 2015-11-07 05:30 -0800
    Re: Memorry error? Eric Sosman <esosman@comcast-dot-net.invalid> - 2015-11-07 08:36 -0500
      Re: Memorry error? Alla _ <modelling.data@gmail.com> - 2015-11-07 06:43 -0800
        Re: Memorry error? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-11-07 17:22 +0000
  Re: Memorry error? "Osmium" <r124c4u102@comcast.net> - 2015-11-07 07:33 -0600
  Re: Memorry error? Alla _ <modelling.data@gmail.com> - 2015-11-07 06:47 -0800
    Re: Memorry error? Eric Sosman <esosman@comcast-dot-net.invalid> - 2015-11-07 10:36 -0500
    Re: Memorry error? Keith Thompson <kst-u@mib.org> - 2015-11-07 13:37 -0800
    Re: Memorry error? Barry Schwarz <schwarzb@dqel.com> - 2015-11-07 16:26 -0800
      Re: Memorry error? Alla _ <modelling.data@gmail.com> - 2015-11-08 23:03 -0800
        Re: Memorry error? Barry Schwarz <schwarzb@dqel.com> - 2015-11-09 01:01 -0800
          Re: Memorry error? Keith Thompson <kst-u@mib.org> - 2015-11-09 08:27 -0800
            Re: Memorry error? raltbos@xs4all.nl (Richard Bos) - 2015-11-17 22:23 +0000
              Re: Memorry error? Keith Thompson <kst-u@mib.org> - 2015-11-17 15:31 -0800
                Re: Memorry error? raltbos@xs4all.nl (Richard Bos) - 2015-11-19 10:41 +0000
      Re: Memorry error? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2015-11-09 10:26 +0000

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