After getting some response from lkml we are ready for
work on new version of POSIX message queues.
Main difference (as Christoph Hellwig suggested) would be
implementing it as a virtual filesystem (based on tmpfs and
parts of Jakub Jelinek code).
I think that we can agree that idea of moving whole stuff to
user space isn't good. There is still a problem with SIGEV_THREAD
version of notification but after (brief) looking into NPTL it
should be possible to implement (in difference to NGPT)
So our question is:
Is above version acceptable for Linux kernel?
Main advantages of such approach are: no need for new
system call and no mess in fork/exit.