rt_task_inquire() equivalent for POSIX ?

rt_task_inquire() equivalent for POSIX ?

[Pierre FICHEUX]

Hi,

Is there a way to get the Xenomai thread "pid" with POSIX API ? I didn't
see anything in the "thread management" section.

thx

-- 

Pierre FICHEUX -/- CTO Smile ECS, France -\- pierre.ficheux@smile.fr
                             http://www.smile.fr
                             https://smile.eu/fr/offres/embarque-iot
I would love to change the world, but they won't give me the source code

Re: rt_task_inquire() equivalent for POSIX ?

[Lowell Gilbert]

Pierre FICHEUX via Xenomai <xenomai@xenomai.org> writes:

> Is there a way to get the Xenomai thread "pid" with POSIX API ? I didn't
> see anything in the "thread management" section.

getpid()?

Re: rt_task_inquire() equivalent for POSIX ?

[Pierre FICHEUX]

I've tried it but got the pid of the "main" thread not the RT one (that's
normal...).

regards

Le jeu. 7 nov. 2019 à 01:20, Lowell Gilbert <kludge@be-well.ilk.org> a
écrit :

> Pierre FICHEUX via Xenomai <xenomai@xenomai.org> writes:
>
> > Is there a way to get the Xenomai thread "pid" with POSIX API ? I didn't
> > see anything in the "thread management" section.
>
> getpid()?
>


-- 

Pierre FICHEUX -/- CTO Smile ECS, France -\- pierre.ficheux@smile.fr
                             http://www.smile.fr
                             https://smile.eu/fr/offres/embarque-iot
I would love to change the world, but they won't give me the source code

Re: rt_task_inquire() equivalent for POSIX ?

[Julien Blanc]

Le jeudi 07 novembre 2019 à 06:47 +0100, Pierre FICHEUX via Xenomai a
écrit :
> I've tried it but got the pid of the "main" thread not the RT one
> (that's
> normal...).
> 

extern "C"
{
        int cobalt_thread_pid(pthread_t);
}

int tid = cobalt_thread_pid(pthread_self())

but i’m not sure what you mean by the cobalt thread id vs posix thread
id. IIRC they have the same value (ie, syscal(__NR_gettid) would give
the same value (for rt threads), maybe at the expense of a mode
switch).

Regards,

Julien Blanc

Re: rt_task_inquire() equivalent for POSIX ?

[Philippe Gerum]

On 2019-11-07 08:56, Julien Blanc via Xenomai wrote:
> Le jeudi 07 novembre 2019 à 06:47 +0100, Pierre FICHEUX via Xenomai a
> écrit :
>> I've tried it but got the pid of the "main" thread not the RT one
>> (that's
>> normal...).
>>
> 
> extern "C"
> {
>         int cobalt_thread_pid(pthread_t);
> }
> 
> int tid = cobalt_thread_pid(pthread_self())
> 
> but i’m not sure what you mean by the cobalt thread id vs posix thread
> id. IIRC they have the same value (ie, syscal(__NR_gettid) would give
> the same value (for rt threads), maybe at the expense of a mode
> switch).

This may be worth a read for context:
http://man7.org/linux/man-pages/man2/gettid.2.html

cobalt_thread_pid() translates POSIX thread identifiers to kernel thread identifiers some Linux-specific calls need (e.g. thread-directed signals).

-- 
Philippe.

Re: rt_task_inquire() equivalent for POSIX ?

[Pierre FICHEUX]

Thx a lot, works fine with cobalt_thread_pid() !

regards



Le jeu. 7 nov. 2019 à 09:44, Philippe Gerum <rpm@xenomai.org> a écrit :

> On 2019-11-07 08:56, Julien Blanc via Xenomai wrote:
> > Le jeudi 07 novembre 2019 à 06:47 +0100, Pierre FICHEUX via Xenomai a
> > écrit :
> >> I've tried it but got the pid of the "main" thread not the RT one
> >> (that's
> >> normal...).
> >>
> >
> > extern "C"
> > {
> >         int cobalt_thread_pid(pthread_t);
> > }
> >
> > int tid = cobalt_thread_pid(pthread_self())
> >
> > but i’m not sure what you mean by the cobalt thread id vs posix thread
> > id. IIRC they have the same value (ie, syscal(__NR_gettid) would give
> > the same value (for rt threads), maybe at the expense of a mode
> > switch).
>
> This may be worth a read for context:
> http://man7.org/linux/man-pages/man2/gettid.2.html
>
> cobalt_thread_pid() translates POSIX thread identifiers to kernel thread
> identifiers some Linux-specific calls need (e.g. thread-directed signals).
>
> --
> Philippe.
>


-- 

Pierre FICHEUX -/- CTO Smile ECS, France -\- pierre.ficheux@smile.fr
                             http://www.smile.fr
                             https://smile.eu/fr/offres/embarque-iot
I would love to change the world, but they won't give me the source code

Re: rt_task_inquire() equivalent for POSIX ?

[Steve Freyder]

On 11/6/2019 3:04 PM, Pierre FICHEUX via Xenomai wrote:
> Hi,
>
> Is there a way to get the Xenomai thread "pid" with POSIX API ? I didn't
> see anything in the "thread management" section.
>
> thx
>
Hi,

This file:

https://xenomai.org/documentation/xenomai-3/pdf/xeno3prm.pdf

makes several references to pthread_self() which implies that's the way 
to do what you are looking for here.

However (to your point), it doesn't explicitly document (in section 6.60 
Thread management) pthread_self() itself, whereas this file:

https://xenomai.org/documentation/xenomai-2.6/pdf/posix-api.pdf

in section 3.12.3 documents pthread_self() along with pthread_create() 
and the other "POSIX thread management" functions.

Perhaps when the 3.0 documentation was written, there was a decision 
made to not document any of the "standard POSIX thread management" 
functions unless there was also an RT variant of the function (sitting 
behind a wrapper) which had behaviour beyond what one could expect to 
find in the standard (non RT) POSIX documentation.  Perhaps there's a 
statement to that effect somewhere in the Xenomai-3 documentation, and 
if not, maybe there should be.

Regards,
Steve