> -----Original Message----- > From: Clemens Ladisch [mailto:clem...@ladisch.de] > Sent: Friday, January 31, 2014 4:54 PM > To: Network Nut > Cc: 'Austin S. Hemmelgarn'; linux-kernel@vger.kernel.org > Subject: Re: WaitForMultipleObjects/etc. In Kernel > > Network Nut wrote: > >> Assuming that you're porting to mainline distributions (and not > >> embedded devices), named SHM segments are accessible (providing the > >> accessing process has correct permissions) under /dev/shm. You just > >> need to make sure that you create the segment with the right > >> permissions for the other processes to access it. > > > > I already know how to do named shared memory between two processes. > I only included that to describe my overall problem. > > > > The problem that I am having is how I can make three totally-independent > processes interact: > > > > 1. M is a master process that creates a semaphore. > > 2. P1 is a process that operates against the semaphore. > > 3. P2 is a process that operates against the semaphore. > > 4. It is not permissible that M be responsible for launching P1 or P2. > > 5. The semaphore, one way or another, must allow itself to be > > specified as one of the synchronization primitives in epoll_wait() > > This general problem descripton does not say anything more than your first > mail. > > Use eventfd. To share it, use a Unix domain socket created by M. (This > socket must be created at a well-known path. shm_open() works similarly, > but that it creates a file in a RAM disk and mmap()s it is just an > implementation detail.)
How do I create the socket at "well-known path"? Regards, -Nut -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/