From mboxrd@z Thu Jan  1 00:00:00 1970
Subject: Re: rt_task_unblock() POSIX alternative
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From: Jan Kiszka <jan.kiszka@siemens.com>
Message-ID: <6a6aed9a-c2af-f498-4e27-bde61646a395@siemens.com>
Date: Tue, 14 Apr 2020 13:01:58 +0200
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To: Richard Weinberger <richard.weinberger@gmail.com>
Cc: =?UTF-8?Q?Petr_=c4=8cervenka?= <grugh@centrum.cz>, Xenomai <xenomai@xenomai.org>

On 14.04.20 12:56, Richard Weinberger wrote:
> On Tue, Apr 14, 2020 at 12:44 PM Jan Kiszka <jan.kiszka@siemens.com> wrote:
> 
>>> While we are here, is there a guarantee that rt_task_unblock() can unblock
>>> a thread in every situation?
>>> I have a large Xenomai 2 application on my desk which seems to assumes that.
>>
>> IIRC, it does so for the native/alchemy API.
>>
>>>
>>> As far as I understand it, unblocking tasks is best effort.
>>> /me has pthread_mutex_lock() in mind which must not return -EINTR as
>>> required by POSIX.
>>>
>>
>> Well, when mixing APIs, you can end up in such conflicting goals, indeed.
> 
> I fear more about Xenomai internals which are now based on POSIX APIs.
> IIRC we talked regarding this issue some time ago.
> 
> Found the mail:
> https://www.xenomai.org/pipermail/xenomai/2019-July/041221.html

Indeed, there is a todo...

Jan

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