[Xenomai-help] Using rtdm_irq_request from user-space.

[Xenomai-help] Using rtdm_irq_request from user-space.

[Victor Alvidrez]

Hello.

I am trying to a write simple program that can listen for interrupts 
produced by the keyboard in user-space.
At first I tried to do this using the native API, however I figured out 
that this functionality is turned off by default.  So I decided to use 
the rtdm API.

I wrote the code using the rtdm_irq_* related functions/variables and 
included the <rtdm/rtdm.h> header file.

However, upon trying to compile I get a bunch of undefined reference 
errors.  I read through the rtdm.h file and found that there are no 
definitions of rtdm_irq* related variables or function declarations.  
All of these things are defined in <rtdm/rtdm_driver.h>, which you 
cannot include in non-kernel code.

I guess it is pretty obvious that I cannot do this from user space... 
but maybe I am missing something?

The rtdm API manual includes a "Environments:This service can be called 
from:" section.  And the function "rtdm_irq_request" lists "User-space 
task (RT, non-RT)".  Doesn't this mean that it can be called from a 
user-space program?

Thanks for any info you can provide.

Running Ubuntu with Xenomai-2.5.5.2, linux kernel 2.6.32 .

Re: [Xenomai-help] Using rtdm_irq_request from user-space.

[Gilles Chanteperdrix]

On 10/17/2011 07:05 PM, Victor Alvidrez wrote:
> Hello.
> 
> I am trying to a write simple program that can listen for interrupts 
> produced by the keyboard in user-space.
> At first I tried to do this using the native API, however I figured out 
> that this functionality is turned off by default.  So I decided to use 
> the rtdm API.
> 
> I wrote the code using the rtdm_irq_* related functions/variables and 
> included the <rtdm/rtdm.h> header file.
> 
> However, upon trying to compile I get a bunch of undefined reference 
> errors.  I read through the rtdm.h file and found that there are no 
> definitions of rtdm_irq* related variables or function declarations.  
> All of these things are defined in <rtdm/rtdm_driver.h>, which you 
> cannot include in non-kernel code.
> 
> I guess it is pretty obvious that I cannot do this from user space... 
> but maybe I am missing something?


Yes.

> 
> The rtdm API manual includes a "Environments:This service can be called 
> from:" section.  And the function "rtdm_irq_request" lists "User-space 
> task (RT, non-RT)".  Doesn't this mean that it can be called from a 
> user-space program?
> 
> Thanks for any info you can provide.

This means that it can be called from the context of an ioctl emitted by
a user-space task (either RT or non RT). The RTDM skin is a kernel-only
skin.

-- 
                                                                Gilles.