On 08/11/2012 03:09 AM, H. Peter Anvin wrote: > On 08/10/2012 12:28 PM, Alan Cox wrote: >> Explicitly for Linux yes - this is not generally true of the AF_UNIX >> socket domain and even the permissions aspect isn't guaranteed to be >> supported on some BSD environments ! > > Yes, but let's worry about what the Linux behavior should be. > >> The name is however just a proxy for the socket itself. You don't even >> get a device node in the usual sense or the same inode in the file system >> space. > > > No, but it is looked up the same way any other inode is (the difference > between FIFOs and sockets is that sockets have separate connections, > which is also why open() on sockets would be nice.) > > However, there is a fundamental difference between AF_UNIX sockets and > open(), and that is how the pathname is delivered. It thus would make > more sense to provide the openat()-like information in struct > sockaddr_un, but that may be very hard to do in a sensible way. In that > sense it perhaps would be cleaner to be able to do an open[at]() on the > socket node with O_PATH (perhaps there should be an O_SOCKET option, > even?) and pass the resulting file descriptor to bind() or connect(). I vote for this (openat + O_WHATEVER on a unix socket) as well. It will help us in checkpoint-restore, making handling of overmounted/unlinked sockets much cleaner. > -hpa Thanks, Pavel -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
