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Date: Thu, 22 Jan 2009 22:02:44 +0100
From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
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Subject: Re: [Xenomai-help] xenomai i2c
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To: wcall@domain.hid
Cc: 'Xenomai help' <xenomai@xenomai.org>

Wayne Call wrote:
> Is it possible to read the /sys/bus/i2c/devices/0-0048/temperature
> file using rt_dev_read?  The application is running in the real time
> context.  Even though the device driver is not in the real time
> context, can an application running in the real time context just
> simple access the /sys/bus/i2c/devices files using rt_dev_read and
> rt_dev_write?  The /sys is where the sysfs has been mounted.

No, rt_dev_read/rt_dev_write is for devices created using the RTDM skin,
not for Linux devices or files. When an application running in real-time
context (that is, in primarey mode) reads a Linux file, it switches to
secondary mode, that is to say, it becomes a plain linux task with linux
induced latencies.

-- 
					    Gilles.