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Groups > comp.lang.c > #9263

Re: Hash table implementation.

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James Kuyper <jameskuyper@verizon.net> writes:
> On 08/12/2011 09:15 AM, tom st denis wrote:
>> On Aug 12, 4:47 am, Nobody <nob...@nowhere.com> wrote:
>>> On Thu, 11 Aug 2011 23:55:45 -0700, lolzy wrote:
>>>> Thanks for all your comments. I still have some questions :) :
>>>
>>>> * Why do you prefer malloc() over calloc() ?
>>>
>>> calloc() zeros the allocated memory, which is inefficient if you don't
>>> actually need to do so.
>> 
>> Generally, if you're allocating memory for a struct that has pointers
>> calloc() is your buddy since it'll also NULL the pointers [ya ya
>> rabble rabble, it's portable, let it go].
>
> It will set all there bits zero, which is not necessarily a
> representation of a null pointer. So, no, it is NOT portable.
>
> Similarly, a floating point object with all bits zeros does not
> necessarily represent 0.0, though that does happen to be the case for
> most implementations.
>
> However, you're fine as long as you stick with arithmetic types.

You're fine as long as you stick with *integer* types.  (Floating-point
types are arithmetic.)

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Nokia
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"

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Hash table implementation. lolzy@live.nl - 2011-08-11 10:43 -0700
  Re: Hash table implementation. China Blue Tip Wrench <chine.bleu@yahoo.com> - 2011-08-11 11:25 -0700
  Re: Hash table implementation. Keith Thompson <kst-u@mib.org> - 2011-08-11 11:49 -0700
    Re: Hash table implementation. Ralf Damaschke <rwspam@gmx.de> - 2011-08-11 20:02 +0000
  Re: Hash table implementation. Ike Naar <ike@sverige.freeshell.org> - 2011-08-11 22:02 +0000
  Re: Hash table implementation. "Scott Fluhrer" <sfluhrer@ix.netcom.com> - 2011-08-11 18:14 -0400
    Re: Hash table implementation. lolzy@live.nl - 2011-08-11 23:55 -0700
      Re: Hash table implementation. lolzy@live.nl - 2011-08-12 01:38 -0700
      Re: Hash table implementation. Nobody <nobody@nowhere.com> - 2011-08-12 09:47 +0100
        Re: Hash table implementation. tom st denis <tom@iahu.ca> - 2011-08-12 06:15 -0700
          Re: Hash table implementation. James Kuyper <jameskuyper@verizon.net> - 2011-08-12 11:34 -0400
            Re: Hash table implementation. Keith Thompson <kst-u@mib.org> - 2011-08-12 08:50 -0700
              Re: Hash table implementation. James Kuyper <jameskuyper@verizon.net> - 2011-08-12 12:24 -0400
          Re: Hash table implementation. Keith Thompson <kst-u@mib.org> - 2011-08-12 08:38 -0700
            Re: Hash table implementation. tom st denis <tom@iahu.ca> - 2011-08-12 10:17 -0700
              Re: Hash table implementation. James Kuyper <jameskuyper@verizon.net> - 2011-08-12 13:54 -0400
                Re: Hash table implementation. tom st denis <tom@iahu.ca> - 2011-08-12 11:30 -0700
                Re: Hash table implementation. Seebs <usenet-nospam@seebs.net> - 2011-08-12 20:39 +0000
                Re: Hash table implementation. Keith Thompson <kst-u@mib.org> - 2011-08-12 14:08 -0700
            Re: Hash table implementation. gordonb.4sxmx@burditt.org (Gordon Burditt) - 2011-08-12 20:04 -0500
              Re: Hash table implementation. Keith Thompson <kst-u@mib.org> - 2011-08-12 18:40 -0700
                Re: Hash table implementation. Harald van Dijk <truedfx@gmail.com> - 2011-08-13 12:59 -0700
              Re: Hash table implementation. Seebs <usenet-nospam@seebs.net> - 2011-08-13 02:34 +0000
      Re: Hash table implementation. Ike Naar <ike@iceland.freeshell.org> - 2011-08-12 11:13 +0000
      Re: Hash table implementation. Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-08-12 07:24 -0400
      Re: Hash table implementation. Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2011-08-12 09:27 -0600
      Re: Hash table implementation. Seebs <usenet-nospam@seebs.net> - 2011-08-12 18:37 +0000
      Re: Hash table implementation. Jens Gustedt <Jens.Gustedt@loria.fr> - 2011-08-13 00:08 +0200
        Re: Hash table implementation. Keith Thompson <kst-u@mib.org> - 2011-08-12 15:26 -0700
          Re: Hash table implementation. Jens Gustedt <Jens.Gustedt@loria.fr> - 2011-08-13 15:11 +0200
            Re: Hash table implementation. Keith Thompson <kst-u@mib.org> - 2011-08-13 11:38 -0700
              Re: Hash table implementation. Jens Gustedt <Jens.Gustedt@loria.fr> - 2011-08-13 21:03 +0200
        Re: Hash table implementation. "Herbert Rosenau" <os2guy@pc-rosenau.de> - 2011-08-19 08:17 +0000
          Re: Hash table implementation. Jens Gustedt <jens.gustedt@loria.fr> - 2011-08-19 13:29 +0200
          Re: Hash table implementation. Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-08-19 14:35 +0300
  Re: Hash table implementation. Michael Angelo Ravera <maravera@prodigy.net> - 2011-08-12 02:54 -0700
  Re: Hash table implementation. Rui Maciel <rui.maciel@gmail.com> - 2011-08-13 23:11 +0100
    Re: Hash table implementation. Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-08-14 00:56 +0100
      Re: Hash table implementation. lolzy@live.nl - 2011-08-14 00:11 -0700
        Re: Hash table implementation. Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-08-14 11:57 +0100

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