Re: realloc() - frequency, conditions, or experiences about relocation?

From	Phil Carmody <pc+usenet@asdf.org>
Newsgroups	comp.lang.c
Subject	Re: realloc() - frequency, conditions, or experiences about relocation?
Date	2024-06-28 11:01 +0300
Organization	A noiseless patient Spider
Message-ID	<87le2p5wd9.fsf@fatphil.org> (permalink)
References	(3 earlier) <v54jac$3a4p2$1@raubtier-asyl.eternal-september.org> <v5bbd3$rhao$2@dont-email.me> <875xtyu0kk.fsf@nosuchdomain.example.com> <v5dq2e$1eh23$11@dont-email.me> <87frt1tk0z.fsf@nosuchdomain.example.com>

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Keith Thompson <Keith.S.Thompson+u@gmail.com> writes:
> Suppose you do something like:
>
>     some_type *p = malloc(BIG_VALUE);
>     // ...
>     p = realloc(p, SMALL_VALUE);
>
> ...  If realloc() succeeds and *does* relocate the object, p
> still points to memory that has now been deallocated, and you don't have
> a pointer to the newly allocated memory.

Surely some mistake?

However, such self-assignments are bad for the reasons you state later;
verify, then update.

Phil
-- 
We are no longer hunters and nomads. No longer awed and frightened, as we have
gained some understanding of the world in which we live. As such, we can cast
aside childish remnants from the dawn of our civilization.
-- NotSanguine on SoylentNews, after Eugen Weber in /The Western Tradition/

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Re: realloc() - frequency, conditions, or experiences about relocation? Vir Campestris <vir.campestris@invalid.invalid> - 2024-06-20 21:08 +0100
  Re: realloc() - frequency, conditions, or experiences about relocation? Bonita Montero <Bonita.Montero@gmail.com> - 2024-06-21 21:12 +0200
    Re: realloc() - frequency, conditions, or experiences about relocation? Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-06-24 08:40 +0000
      Re: realloc() - frequency, conditions, or experiences about relocation? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-06-24 02:55 -0700
        Re: realloc() - frequency, conditions, or experiences about relocation? David Brown <david.brown@hesbynett.no> - 2024-06-24 13:40 +0200
          Re: realloc() - frequency, conditions, or experiences about relocation? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2024-06-24 18:50 +0100
            Re: realloc() - frequency, conditions, or experiences about relocation? scott@slp53.sl.home (Scott Lurndal) - 2024-06-24 18:20 +0000
              Re: realloc() - frequency, conditions, or experiences about relocation? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-06-24 14:28 -0700
                Re: realloc() - frequency, conditions, or experiences about relocation? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2024-06-25 00:22 +0100
                Re: realloc() - frequency, conditions, or experiences about relocation? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-06-24 18:31 -0700
            Re: realloc() - frequency, conditions, or experiences about relocation? Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-06-25 07:06 +0000
              Re: realloc() - frequency, conditions, or experiences about relocation? Bonita Montero <Bonita.Montero@gmail.com> - 2024-06-25 10:38 +0200
                Re: realloc() - frequency, conditions, or experiences about relocation? Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-06-26 00:51 +0000
          Re: realloc() - frequency, conditions, or experiences about relocation? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-06-24 12:33 -0700
            Re: realloc() - frequency, conditions, or experiences about relocation? Bonita Montero <Bonita.Montero@gmail.com> - 2024-06-24 21:48 +0200
          Re: realloc() - frequency, conditions, or experiences about relocation? Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-06-24 22:59 +0000
        Re: realloc() - frequency, conditions, or experiences about relocation? Bonita Montero <Bonita.Montero@gmail.com> - 2024-06-24 16:19 +0200
        Re: realloc() - frequency, conditions, or experiences about relocation? Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-06-25 07:02 +0000
          Re: realloc() - frequency, conditions, or experiences about relocation? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-06-25 03:05 -0700
            Re: realloc() - frequency, conditions, or experiences about relocation? Richard Damon <richard@damon-family.org> - 2024-06-25 07:21 -0400
            Re: realloc() - frequency, conditions, or experiences about relocation? Phil Carmody <pc+usenet@asdf.org> - 2024-06-28 11:01 +0300
              Re: realloc() - frequency, conditions, or experiences about relocation? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-06-28 04:04 -0700
            Re: realloc() - frequency, conditions, or experiences about relocation? James Kuyper <jameskuyper@alumni.caltech.edu> - 2024-06-28 06:37 -0400
              Re: realloc() - frequency, conditions, or experiences about relocation? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-06-28 04:05 -0700
          Re: realloc() - frequency, conditions, or experiences about relocation? James Kuyper <jameskuyper@alumni.caltech.edu> - 2024-06-28 06:36 -0400
      Re: realloc() - frequency, conditions, or experiences about relocation? Bonita Montero <Bonita.Montero@gmail.com> - 2024-06-24 16:16 +0200
        Down the hall, past the water cooler, third door on the left... (Was: realloc() - frequency, conditions, or experiences about) relocation? gazelle@shell.xmission.com (Kenny McCormack) - 2024-06-24 15:44 +0000
          Re: Down the hall, past the water cooler, third door on the left... (Was: realloc() - frequency, conditions, or experiences about) relocation? Bonita Montero <Bonita.Montero@gmail.com> - 2024-06-24 20:16 +0200

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