unlimited (was Re: task notepad question)

[Joel Sherrill]

Chris Johns wrote:
> 
> Joel Sherrill wrote:
> 
> > NOTE: The set of POSIX keys is not enlarged if you use unlimited tasks.
> 
> Does the user get the correct error code in the current code ?

What would it be and who would trigger it?  All tasks/threads are
supposed to have a key slot.

> Do any other parts of the POSIX API suffer from this problem or is it
> just threads (tasks!) ?

I think that it is just keys.  I think you can extend the number of
POSIX 
threads.  But keys are different.

> This is also the case with User Extensions and the drivers table. You
> can add drivers after starting, but the number is fixed. Any others ?

I don't think this is that bad a problem.  It is just a configuration
limit.  

> I can raise a PR for this and list all the areas that need to be looked at.
> 
> I have not looked at the POSIX implementation so far :-). Are keys
> handled in one spot ?

As much as anything in RTEMS... see cpukit/posix/src/key*.c.  The
problem
is that there is no event/API hook when the number of tasks/threads
increases.  Look at keycreate.c and you will see the problem.

> --
>   Chris Johns, cjohns at cybertec.com.au

-- 
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