From: Shawn Hargreaves <Shawn AT talula DOT demon DOT co DOT uk>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Contiguous memory allocation
Date: Wed, 23 Jul 1997 19:10:19 +0100
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Gordon Brown writes:
>Does allocating say 1Mb of memory with malloc return a contiguous memory
>array.  I am trying to DMA from a PCI board to host memory and do not
>want to go via conventionial memory if possible.

Almost certainly not, and even if it did, it is unlikely to stay
contiguous (any part of it is liable to get moved around your physical
memory and/or swapped out to disk). The only sure way to implement DMA
is to use a conventional memory buffer. The VDS services would be
another possibility, but they aren't supported by CWSDPMI...


--
Shawn Hargreaves - shawn AT talula DOT demon DOT co DOT uk - http://www.talula.demon.co.uk/
Beauty is a French phonetic corruption of a short cloth neck ornament.