[Xenomai-core] Re: Time representation in RTDM profiles

[Jan Kiszka <jan.kiszka@domain.hid>]

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Sebastian Smolorz wrote:
> Jan Kiszka wrote:
>> the current representation of timeouts and timestamps in RTDM device
>> profiles is inconsistent.
> 
> I would welcome a consistent time value representation above all RTDM 
> profiles, too.
> 
>> In the serial profile we use [u]int64_t 
>> directly, the CAN profile defines its own types called
>> nanosecs_{abs|rel}_t (though they just wrap the int64 ones).
>>
>> What is the idea of nanosecs? Having a way to redefine that type looks
>> nice, but it's unfortunately the ABI, so we cannot easily change it
>> without breaking apps.
> 
> The possibility of redefinition was not the main goal here. As you mentioned 
> it would be problematic. No, I introduced nanosecs_abs_t and nanosecs_rel_t 
> because they are more intuitive and more "speaking" to the programmer. The 
> meaning of a variable of such a type is clear at first sight.
> 

Yeah, sounds reasonable to me. Then let's move these typedefs to rtdm.h
and document them as self-explanatory defines of the underlying standard
types, freezing their width and signedness at the same time.

Actually, this would be useful for the driver API of RTDM as well.

Jan


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