Re: [boost] [interprocess] Boost.Thread developers willing to help on interprocess condition vars?

From: Ion Gaztañaga (igaztanaga_at_[hidden])
Date: 2007-09-28 16:59:53

Anthony Williams wrote:
> However, I would not expect the mutex to survive a reboot --- there might
> still be data in the file, but I would expect a process-shared mutex to have
> at least some portion that was a handle to a kernel object, and the kernel
> object would go away with a reboot.
> 
> I expect the same to be true of condition variables. There is certainly
> nothing in the POSIX spec that says you can save a mutex to disk and read it
> back again. In fact, there is explicit wording in the rationale to suggest
> that some implementations may just store a pointer to the actual data
> structure --- in which case, writing it to disk and reading it back is not
> going to work, as the pointer will be invalid.

Even if POSIX does not officially guarantee it, I think filesystem 
persistence is very useful for mutexes, like the message queue example 
shows. Interprocess users are pretty happy with it. Until now all 
systems I've found that support process-shared mutexes do support the 
mapped files option.

I wouldn't request your help if the task was easy ;-)

> Anthony

Regards,

Ion