malloc does not return null when out of memory

[Muttley]

   Yes, I thought briefly about something like this.
   Then I thought 'there's a race condition'.
   Then I realised that other processes might not link against this
   malloc.
   Then I realised the race condition doesn't even matter; processes will
   still be killed, as the kernel doesn't care that you're still in
   malloc() when the overcommitted memory is touched, it just knows
   you've touched it and there's no actual memory there. This will result
   in far more processes being killed. I believe that's a bad thing.
   Any patch for this is going to have to be in kernelland not userland.
   Cheers,
   Matt

   From: "Chuck Swiger" <cswiger at mac.com>
   Date: 24/07/03 15:16
   I don't think the following is a particularly good idea, as the
   existing prezero
   ('Z') or junk ('J') options will also serve to reference memory and
   prevent
   the "memory overcommit issue", but:
   <patch to touch memory just after it's sbrk'd>