[okl4-developer] Thread ids and caps in OKL4 2.1

[Joshua Root]

Geoffrey Lee wrote:
> On Wed, Jul 09, 2008 at 04:27:44PM +1000, Joshua Root wrote:
>> Hi folks,
>>
> 
> Josh - 
> 
>> I'd like to get some things clarified regarding the new IPC security 
>> model in OKL4 2.1. Apologies if the answers to these questions are in 
>> the docs, but I haven't been able to locate them.
>>
>> * Does the root server need to explicitly create caps in the root clist 
>> before it can IPC other threads? If so, how is this done? 
>> (L4_CreateIpcCap()'s description seems to indicate that it actually just 
>> copies an existing cap between clists?)

^ No insights on this?

>> * When my root server receives a message in its main loop, the 'from' 
>> tid usually seems to be 0x80000002, which I'm told is a reply cap (the 
>> docs don't seem to mention this BTW). How can I find out the sender's 
>> real global thread id?
> 
> Please have a look at this brief explanation:
> 
> http://wiki.ok-labs.com/ReplyCaps

Well pointed out. That does indeed explain that the from tid is a reply 
cap. :-)

> Can you please let us know more about the operation that you 
> are trying to perform?  Is obtaining the thread identifier
> for debugging purposes, or is there some other need for it?

Debugging purposes, and message dispatch. The skeleton OS is very simple 
(read: broken) and doesn't have separate server threads for different 
things.

- Josh