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From: =?ISO-8859-1?Q?Ren=E9_Berber?= <r DOT berber AT computer DOT org>
Subject:  Re: mmap() on 64K aligned address fails
Date:  Sat, 26 Nov 2005 15:19:06 -0600
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Samuel Thibault wrote:
[snip]
> This seems odd. In the cygwin case, pagesize() would not be sufficient ??

No, in windows there is a requirement that mmap uses memory aligned to 64k =
(the
infamous granularity).

> And anyway, it should rather be=20
>    data2 =3D (char *) malloc (2 * 16 * pagesize);
> Not only 16 (since it is further 16*pagesize -aligned).

It's enough to allocate 16 x pagesize to use one page for mmap-ing (like Co=
rinna
said in one message 15/16 pages will not be aligned -- but one will).  If y=
ou
see the intermediate results I printed, data2 is re-aligned to 64k correctl=
y.

Anyway, I still don't know why mmap() failded.
--=20
Ren=E9 Berber


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