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Re: array-size/malloc limit and strlen() failure

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

(snip, someone wrote)
>> However, you can write your own strlen() function which takes some of that 
>> into account, if you're that paranoid about it (although beware that if the 
>> address space is 64-bits, wrap-around might be impossible).
 
> You can't *portably* write such a strlen() function.  There is no
> portable way to tell whether a given non-null address is valid or not.

Hmm. You can check to see if p++ is less than p. If that happens before
you find the '\0' in the string, you should probably stop looking.
 
> In any case, strlen isn't the problem here.  If you can allocate an
> array and ensure that it contains a null byte somewhere, you can run
> strlen on it.

-- glen

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array-size/malloc limit and strlen() failure jay <arnuld.mizong@gmail.com> - 2014-04-01 23:31 -0700
  Re: array-size/malloc limit and strlen() failure Xavier Roche <xroche@free.fr.NOSPAM.invalid> - 2014-04-02 08:47 +0200
  Re: array-size/malloc limit and strlen() failure Kaz Kylheku <kaz@kylheku.com> - 2014-04-02 07:36 +0000
  Re: array-size/malloc limit and strlen() failure "BartC" <bc@freeuk.com> - 2014-04-02 10:10 +0100
    Re: array-size/malloc limit and strlen() failure Keith Thompson <kst-u@mib.org> - 2014-04-02 08:11 -0700
      Re: array-size/malloc limit and strlen() failure glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-02 19:03 +0000
        Re: array-size/malloc limit and strlen() failure James Kuyper <jameskuyper@verizon.net> - 2014-04-02 15:48 -0400
          Re: array-size/malloc limit and strlen() failure Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-04-02 14:42 -0700
            Re: array-size/malloc limit and strlen() failure Keith Thompson <kst-u@mib.org> - 2014-04-02 15:14 -0700
        Re: array-size/malloc limit and strlen() failure Keith Thompson <kst-u@mib.org> - 2014-04-02 14:55 -0700
          Re: array-size/malloc limit and strlen() failure glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-02 23:42 +0000
  Re: array-size/malloc limit and strlen() failure Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-04-02 02:34 -0700
  Re: array-size/malloc limit and strlen() failure James Kuyper <jameskuyper@verizon.net> - 2014-04-02 07:40 -0400
    Re: array-size/malloc limit and strlen() failure Thomas Jahns <jahns@idontlikespam.dkrz.de> - 2014-04-02 13:52 +0200
    Re: array-size/malloc limit and strlen() failure Keith Thompson <kst-u@mib.org> - 2014-04-02 08:21 -0700
      Re: array-size/malloc limit and strlen() failure James Kuyper <jameskuyper@verizon.net> - 2014-04-02 11:30 -0400
      Re: array-size/malloc limit and strlen() failure glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-02 19:26 +0000
        Re: array-size/malloc limit and strlen() failure "BartC" <bc@freeuk.com> - 2014-04-02 20:39 +0100
        Re: array-size/malloc limit and strlen() failure Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2014-04-02 14:39 -0600
        Re: array-size/malloc limit and strlen() failure Keith Thompson <kst-u@mib.org> - 2014-04-02 15:03 -0700
          Re: array-size/malloc limit and strlen() failure Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-04-03 01:11 -0700
            Re: array-size/malloc limit and strlen() failure Ike Naar <ike@iceland.freeshell.org> - 2014-04-03 14:27 +0000
              Re: array-size/malloc limit and strlen() failure James Kuyper <jameskuyper@verizon.net> - 2014-04-03 17:56 -0400
            Re: array-size/malloc limit and strlen() failure Keith Thompson <kst-u@mib.org> - 2014-04-03 08:18 -0700
              Re: array-size/malloc limit and strlen() failure gazelle@shell.xmission.com (Kenny McCormack) - 2014-04-03 15:30 +0000
      Re: array-size/malloc limit and strlen() failure Stephen Sprunk <stephen@sprunk.org> - 2014-04-03 00:33 -0500

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