Re: [ECOS] cyg_io_write

[Bob Koninckx <bob dot koninckx at mech dot kuleuven dot ac dot be>]

Gary Thomas wrote:
> 
> On 28-Jun-00 Dave Airlie wrote:
> >
> > Can I call cyg_io_write from with a cyg_io_write? as in my app calls a
> > virtual cyg_io_write which then calls a cyg_io_write on a real serial
> > port... does this sound like something I really shouldn't be doing, it
> > doesn't seem to work, but the problems I've been having I would be loathe
> > to blame eCos before asking :-)
> >
> 
> I don't see any reason why it wouldn't work.  This function should be
> reentrant as well as serially reusable.


Make sure you never lock an already locked mutex. I remember spending
quite some time searching for a deadlock caused by this .... (I am not
sure it will happen in your case though)

Might be an idea do modify the cyg_mutex_t behaviour in such a way that
a call to cyg_mutexc_lock doesnt do anything if it is called from the
thread that already owns the lock. Similar to what "How are they called
again ??" does with their CRITICAL_SECTION objects. Cygnus folks ??

Regards,
Bob

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 ir. Bob Koninckx
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