Re: [Xenomai-help] shm_open returns errno 38 - function not implemented

[Yigal Goldberger <yigal_gold@domain.hid>]

Gilles,
Thanks for the answer.

I need shared memory only between user space applications , so I do prefer the second option. (our system is stable and we're satisfied from the performance , so we'd like to make as little changes as possible at this mature stage of the project ).
Can you advise me how to get the right version of the glibc (is it a stand alone change , simply replacing the glibc file , or do I need to make other changes ?)

Thanks again to the Xenomai operation , and to you personaly for your support !
Yigal Goldberger .


--- On Fri, 10/16/09, Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.orgg> wrote:

> From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
> Subject: Re: [Xenomai-help] shm_open returns errno 38 - function not implemented
> To: "Yigal Goldberger" <yigal_gold@domain.hid>
> Cc: xenomai@xenomai.org
> Date: Friday, October 16, 2009, 12:00 PM
> Yigal Goldberger wrote:
> > Hi again,
> > 
> > I'm trying to create a shared memory area .
> > The system is a powerpc based board running linux
> kernel 2.6.29.4
> > and Xenomai 2.4.8 .
> > When I call shm_open from user space I get error 38 -
> function not implemented .
> 
> Normally, xenomai's shm_open tries to use the xenomai posix
> skin service
> first, and if it fails (because the shared memory option
> was not enabled
> in the posix skin configuration), falls back to linux
> service.
> 
> You get this error because:
> - Xenomai posix skin's shared memory services are not
> enabled;
> - your glibc does not support posix shared memory services
> (you can
> check this in xenomai's config.log, there is a test
> detecting it).
> 
> Now, Xenomai posix skins's shared memory services are to be
> used if you
> want to share memory between a kernel-space real-time posix
> application,
> and a user-space real-time posix application.
> 
> So, if this is what you want to do, enable the xenomai
> posix skin shared
> memory services in the kernel configuration (and please
> upgrade to
> xenomai 2.4.9.1, because some bugs in the shared memory
> support were
> fixed recently). If you want to share memory between two
> user-space
> applications, you can also use xenomai shared memory
> services, but you
> are probably better of upgrading your glibc to a glibc
> which support
> posix shared memories.
> 
> -- 
>                
>                
>           Gilles
> 
>