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Re: heap memory indexed as an array

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On Wed, 20 Mar 2019 04:40:25 GMT, Spiros Bousbouras <spibou@gmail.com>
wrote:

>But you don't get to do error checking either and if there isn't enough
>memory to allocate the array , the programme will probably crash with an
>uninformative error message.

Well, maybe. On some contemporary operating systems, a malloc return
value of non-null does not guarantee that the allocated memory
actually exists. It can appear to succeed, and only explodes when you
try to write to that phantom memory -- and there's no way to trap that
fault in C.

That's not C's fault of course, just something to keep in mind as a C
wright.

I'm not sure how this state of affairs came to be, other than some
misguided pandering to sloppy and lazy programmers. But it seems to be
the new normal. It has one positive(?) side effect, in that you can
usually disable this "feature" in the OS, and this works to rapidly
identify programs written by sloppy and lazy programmers as they begin
spewing ENOMEM faults.

And this is off-topic in CLC. But yes, you can use heap as an array,
because malloc returns a pointer and every pointer is the base of an
array.

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heap memory indexed as an array sinbad <sinbad.sinbad@gmail.com> - 2019-03-19 20:05 -0700
  Re: heap memory indexed as an array Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2019-03-19 21:37 -0600
    Re: heap memory indexed as an array Spiros Bousbouras <spibou@gmail.com> - 2019-03-20 04:40 +0000
      Re: heap memory indexed as an array nobody@example.org (Scott) - 2019-03-20 15:56 +0000
        Re: heap memory indexed as an array scott@slp53.sl.home (Scott Lurndal) - 2019-03-20 16:43 +0000
          Re: heap memory indexed as an array fir <profesor.fir@gmail.com> - 2019-03-20 10:00 -0700
          Re: heap memory indexed as an array William Ahern <william@25thandClement.com> - 2019-03-20 15:07 -0700
            Re: heap memory indexed as an array fir is a sexy shemale <cdalten@gmail.com> - 2019-03-20 23:52 -0700
          Re: heap memory indexed as an array nobody@example.org (Scott) - 2019-03-21 16:50 +0000
            Re: heap memory indexed as an array scott@slp53.sl.home (Scott Lurndal) - 2019-03-21 17:23 +0000
              Re: heap memory indexed as an array nobody@example.org (Scott) - 2019-03-22 04:29 +0000
                OT: crashing malloc [was Re: heap memory indexed as an array] nobody@example.org (Scott) - 2019-03-23 15:27 +0000
                Re: heap memory indexed as an array Spiros Bousbouras <spibou@gmail.com> - 2019-03-23 19:24 +0000
                Re: heap memory indexed as an array Melzzzzz <Melzzzzz@zzzzz.com> - 2019-03-23 20:20 +0000
      Re: heap memory indexed as an array Tim Rentsch <tr.17687@z991.linuxsc.com> - 2019-03-21 22:35 -0700
  Re: heap memory indexed as an array Jorgen Grahn <grahn+nntp@snipabacken.se> - 2019-03-20 07:05 +0000
  Re: heap memory indexed as an array Ben Bacarisse <ben.usenet@bsb.me.uk> - 2019-03-20 12:12 +0000

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