On Tue, Apr 21, 2009 at 09:53:37AM -0800, Larry Dickson wrote: > Hello all, > > As a Samba programming newbie, I've run onto a question that doesn't have an > obvious answer in FAQ or googled literature. I need to lock large numbers of > files on the server, and have Samba open requests block until they are > released. I found references to "blocking locks" in references such as > "Using Samba" (O'Reilly, 1999, 2003) > > http://oreilly.com/catalog/samba/chapter/book/ch05_05.html > > but these refer to range locks, which are overkill for my application (I > only need to check on open, not on every IO). > > Deny modes would seem to fill the bill, but I can't find whether blocking > locks would work for them, and also they do not seem to be Linux-compatible > on the server, and I suspect I may need that for efficiency's sake (a lot of > files are being locked/unlocked). I downloaded samba-latest.tar.gz and > noticed that source/smbd/blocking.c seems to respond to these by setting > LOCK_MAND versions of flock states, which are available only for "sys_flock" > and rumored not to affect normal Linux programming. > > Can file locks block a Samba open request? Can they be set by, or made to > affect, Linux programming on the server (I don't care about NFS file opens, > only local opens on the server)? Does this drive special Samba kernel code, > or does smbd just operate in user space?
File locks can't block an open request. On a Linux kernel you can use file leases to prevent other local opens. Jeremy. -- To unsubscribe from this list go to the following URL and read the instructions: https://lists.samba.org/mailman/options/samba
