sbrk(2) broken

Poul-Henning Kamp phk at
Fri Jan 4 05:28:41 PST 2008

In message <20080104131247.GA17816 at>, Andrey Chernov writes:
>On Fri, Jan 04, 2008 at 12:57:11PM +0000, Poul-Henning Kamp wrote:
>> There is address space allocated to the process (via sbrk/mmap)
>> A subset of this, is address space allocated by the program (via malloc)
>> ...and then there is memory actually in use, which is an entirely different
>> thing, of which we currently only have some kind of clue in the VM
>> system.
>Then, we need sysctl to fetch that "memory actually in use" from the 
>kernel and compare that with getrlimit() which allows malloc() to return 
>0 when needed.

No we don't.

Find a book that explains how Virtual Memory works.

Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk at FreeBSD.ORG         | TCP/IP since RFC 956
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Never attribute to malice what can adequately be explained by incompetence.

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