[bknr-devel] bknr.datastore store lockfile

[Vladimir Sedach]

Hi Hans,

> No, there are no plans to do that, but I'm open to patches that add
> the functionality.  I did not ever see the lack of a lock file as a
> problem, but I see how it is easily possible to seriously mess up a
> store by trying to open it from multiple processes.

One thing I found in building a lock file mechanism for my application
is that there's no way to do it portably in CL, which makes sense
since some details are OS dependent (and even on Unix it might not
work on NFS, etc.). So I don't know of the right way of doing it
(maybe a lock file is not actually the right way), and I'd like to
figure one out before putting any mechanisms in a library.

> Again, this is a problem I have not encountered, but I'm open to
> patches correcting the problem.  Do you have an isolated test case
> that exposes the problem?

I don't really have a test case for this beyond "make a store as
non-root user, put some data in the log (and maybe a snapshot), then
try to open that store as root."

Thank you,
Vladimir