[OpenAFS] another approach for detecting byte-range-lock safeness

Derrick J Brashear shadow@dementia.org
Mon, 25 Dec 2006 20:18:13 -0500 (EST)

On Mon, 25 Dec 2006, Adam Megacz wrote:

> Is Linux the *only* currently-deployed (ie <=1.4.x) AFS client that
> implements client-local byte range locking?
> If so, perhaps I can check what OS is running, use some hardwired
> syscall value if OS==Linux, and use the fork()-and-fcntl(F_SETLK) to
> look for (local) enforcement of byte-range locks if OS!=Linux.
> Any obvious flaws in this?  Has the AFS syscall() value been the same
> on Linux throughout history?

Yes (per hardware platform, yes, anyway) but you'll need to consider the 
afs_ioctl interface (a /proc file) for systems where we couldn't install 
our system call into the reserved-for-it slot.