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Date: Mon, 16 Mar 2009 22:31:33 +0100
From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
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Subject: Re: [Xenomai-help] ENXIO error with large shared memory
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To: Henry Bausley <hbausley@domain.hid>
Cc: xenomai@xenomai.org

Henry Bausley wrote:
> I am trying to map a large shared memory buffer and cannot seem to map 32M.
> I get the error code ENXIO back from the posix skin mmap.
> 
> The code works for
>   ftruncate(prgshmfd, 16777216);
>   pPrgShm = mmap(NULL, 16777216, PROT_READ | PROT_WRITE, MAP_SHARED, prgshmfd, 0);
> but fails if I have
>   ftruncate(prgshmfd, 16777216*2);

What if you checked the return value of ftruncate here ?

>   pPrgShm = mmap(NULL, 16777216*2, PROT_READ | PROT_WRITE, MAP_SHARED, prgshmfd, 0);
> 

-- 
					    Gilles.