Re: [Threads-devel] Mutexes

From: Anthony Williams (anthony_at_[hidden])
Date: 2006-03-02 08:41:42

Roland Schwarz <roland.schwarz_at_[hidden]> writes:

> Another point: Anthony is proposing (as I understood) to have a mutex 
> without
> a destructor. Hmm, how would one release the system mutex resource then?

I am proposing that we have a mutex type without a destructor, *in addition*
to one with a destructor, for mutexes with static storage duration. Such a
mutex will be cleaned up automatically by Windows on program exit:

"When a process terminates, the system automatically closes handles and
deletes objects created by the process" (from System Services/Windows System
Information/Handles and Objects/About Handles and Objects/Object Interface in
the platform SDK docs)

It is legal to destroy a locked mutex object. The assert does not check for
that case --- it checks whether CloseHandle failed. CloseHandle will fail if
the handle is invalid, which therefore indicates a corrupt system, so it is a
good idea to terminate the app.

Anthony
-- 
Anthony Williams
Software Developer
Just Software Solutions Ltd
http://www.justsoftwaresolutions.co.uk