[OpenAFS] Re: safe+portable way to determine if byte-range-locking is dangerous?

Russ Allbery rra@stanford.edu
Fri, 15 Dec 2006 18:13:42 -0800

Adam Megacz <megacz@cs.berkeley.edu> writes:
> Marcus Watts <mdw@umich.edu> writes:

>> Does sqlite make any attempt today to see if byte range locking works,

> Sure -- it checks whether fcntl(fd,F_SETLK,&flock)==0.

> ...unless you mean actually checking at runtime to see if it's possible
> to violate a lock that has been "granted".  Interesting.  This is the
> most promising suggestion I've heard so far.  I'm going to run this by
> the sqlite people.

I thought, on Linux at least, that some combination of the cache manager
and the generic file system layer caused byte-range locking to work on the
local host even though other hosts wouldn't see the lock.

Russ Allbery (rra@stanford.edu)             <http://www.eyrie.org/~eagle/>