Re: [boost] mutex feature diagram

From: John Maddock (John_Maddock_at_[hidden])
Date: 2000-08-27 05:41:00

>  ... (everyone speak up if there is a platform you care about)

BeOS 5 may be an interesting port: as I understand it Be has one mutex type
and that's it - I believe that there is also an attempt at providing a
condition variable (as an unsupported extension - I don't know how many
bugs it has!).  I guess if it's possible to port to there, it should be
possible to go anywhere?

>2. What features in the diagram are "portable", which are not.
>   - The owner priority options "ceiling" and "inherited" are not
>     available in older versions of pthreads, I'll have to look into 
>     the exact status here.

Yes, ideally I'd like a big table listing all the platform native types and
their feature sets, then all you have to do is draw a line through the
feature set that is best supported and say "thats it!"  Of course I don't
want to be the one that constructs that table :-)

BTW I don't necessarily see there being just one mutex type - there may be
multiple slices through the feature diagram, some more portable than
others.

Many of the features can also be emulated on platforms that don't natively
support them; priority adjustment probably being one of the easiest to
emulate, provided we have some coherent interface to the thread itself.

Finally all the features in the diagram should be experimentally testable -
however to write a portable test suite we would also need a portable thread
creation/management interface.

- John.