X-Spam-Check-By: sourceware.org To: cygwin@cygwin.com From: =?ISO-8859-1?Q?Ren=E9_Berber?= Subject: Re: mmap() on 64K aligned address fails Date: Sat, 26 Nov 2005 15:19:06 -0600 Lines: 23 Message-ID: References: <20051126180331.GI5074@bouh.residence.ens-lyon.fr> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable User-Agent: Mozilla Thunderbird 1.0.2 (Windows/20050317) In-Reply-To: <20051126180331.GI5074@bouh.residence.ens-lyon.fr> OpenPGP: url=ldap://keyserver.pgp.com X-IsSubscribed: yes Mailing-List: contact cygwin-help@cygwin.com; run by ezmlm Precedence: bulk List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-owner@cygwin.com Mail-Followup-To: cygwin@cygwin.com Delivered-To: mailing list cygwin@cygwin.com 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 -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Problem reports: http://cygwin.com/problems.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/