From: arnold@skeeve.com (arnold@skeeve.com)
Subject: [TUHS] Did realloc ever zero the new memory?
Date: Fri, 11 Sep 2015 00:30:36 -0600 [thread overview]
Message-ID: <201509110630.t8B6UaYF010131@freefriends.org> (raw)
In-Reply-To: <CAC20D2P_Gw-YKP8EHASFToTe_W0nfdcJabQ6_aJYnX0BhnPvng@mail.gmail.com>
> On Thu, Sep 10, 2015 at 4:21 PM, Larry McVoy <lm at mcvoy.com> wrote:
>
> > Am I the only one that remembers realloc() being buggy on some systems?
Clem Cole <clemc at ccc.com> wrote:
> Amen... it was rarely useful. I always found realloc to one of the
> part I could never trust. I do remember what you got back from any of the
> malloc calls could vary widely. Particularly pre-ANSI C and working on
> non-UNIX systems.
I would not say this applies today. The GLIBC realloc is very effective.
The place where I see this is in gawk, which special cases
a = a b # concatenate string b onto the end of string a
By using realloc to grow the contents of a and copying b's contents
onto the end I see a huge speedup over the dance of
char *p malloc(length(a) + length(b))
copy in a
copy in b
free old a
make a point at new storage
Arnold
next prev parent reply other threads:[~2015-09-11 6:30 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-09-10 19:52 David
2015-09-10 20:10 ` Jim Capp
2015-09-10 20:21 ` Larry McVoy
2015-09-10 20:22 ` David
2015-09-10 20:27 ` Larry McVoy
2015-09-10 20:29 ` David
2015-09-10 20:41 ` Clem Cole
2015-09-11 6:30 ` arnold [this message]
2015-09-11 14:36 ` Clem Cole
2015-09-11 0:13 ` Dave Horsfall
2015-09-11 15:41 Norman Wilson
2015-09-11 16:44 ` scj
[not found] <1441931343.25526.for-standards-violators@oclsc.org>
2015-09-12 5:16 ` Dave Horsfall
2015-09-12 6:47 ` Greg 'groggy' Lehey
2015-09-13 0:32 Doug McIlroy
2015-09-13 1:15 ` Larry McVoy
2015-09-13 6:09 ` Dave Horsfall
2015-09-14 3:20 ` Greg 'groggy' Lehey
2015-09-17 4:42 ` Jonathan Gevaryahu
2015-09-13 7:06 ` markus schnalke
2015-09-13 10:32 ` Dave Horsfall
2015-09-13 11:06 ` markus schnalke
2015-09-13 12:13 ` Derek Fawcus
2015-09-13 13:45 ` John Cowan
2015-09-13 1:30 ` Random832
2015-09-13 2:29 ` Charles Anthony
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