Xref: utzoo comp.std.c:1002 comp.lang.c:17394
Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!csd4.milw.wisc.edu!lll-winken!uunet!ingr!crossgl
From: crossgl@ingr.com (Gordon Cross)
Newsgroups: comp.std.c,comp.lang.c
Subject: Re: realloc
Message-ID: <4799@ingr.com>
Date: 3 Apr 89 14:29:49 GMT
References: <681@sdrc.UUCP> <3229@goofy.megatest.UUCP>
Reply-To: crossgl@ingr.UUCP (Gordon Cross)
Organization: Intergraph Corp. Huntsville, AL
Lines: 33

In article <3229@goofy.megatest.UUCP> djones@megatest.UUCP (Dave Jones) writes:
>
>The realloc((char*)0, size) thing was bad enough. What's this all
>about?
>Can anyone suggest a legitimate reason why they would want to do such
>a thing?

Yes!!  Imagine a situation wherein you are dynamically adjusting your memory
requirements (both up and down) to hold data which may grow and shrink in
its storage requirements.  This behavior eliminates special handling of the
boundary case when the size periodically goes to zero!!  I've desired this
behavior many times and I solved it with:

char *myrealloc (ptr, size)

char     *ptr;
unsigned  size;
{
  if (!ptr)
    return malloc (size);
  if (!size) {
    free (ptr);
    return 0;
  }
  return realloc (ptr, size);
}

I am VERY pleased that ANSI choose to require this behavior...
-- 

Gordon Cross             UUCP:      uunet!ingr!crossgl     "all opinions are
111 Westminister Way     INTERNET:  crossgl@ingr.com        mine and not those
Madison, AL 35758        MA BELL:   (205) 772-7842          of my employer."