Re: [Xenomai-help] RTDM or native Xenomai API

[Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>]

On 04/16/2012 01:47 AM, Gilles Chanteperdrix wrote:
> On 04/16/2012 12:53 AM, Andrey Nechypurenko wrote:
>> Hi Gilles,
>>
>> Thank you very much for such low-latency reply! :-)
>>
>>> RTDM is the API of choice for developing drivers for real-time
>>> applications using xenomai.
>>
>> Please correct me if I just misunderstand something here, but as I
>> understand, RTDM is an abstraction layer with concrete implementation
>> using xenomai API. As stated in the referenced paper from Jan Kiszka,
>> the original reason for introducing this layer was to achieve
>> portability across different RT solutions for Linux. Since that time,
>> a lot of considered RT solutions becomes irrelevant. In fact, I would
>> say, there are only Xenomai and preempt_rt. If this assumption is
>> true, then I can not see the advantages of the additional layer unless
>> it is more then just an abstraction layer. Does RTDM API makes certain
>> tasks easier/better compared to the similar native xenomai API? Just
>> to give concrete example - what is the advantage of using
>> rtdm_task_init() vs. rt_task_create or xnintr_init() vs.
>> rtdm_irq_request()?
> 
> The native API is designed to write applications, not drivers. The RTDM
> API is designed to write drivers. Using the native API in user-space is
> deprecated, the native API is made for user-space.

Using the native API in *kernel-space* is deprecated, the native API is
made for user-space. Writing applications in kernel-space is not what we
recommend, as much as writing drivers in user-space.

-- 
                                                                Gilles.