Re: [exim] spec.txt, NFS and file locking

On 13/05/2020 13:56, Vincent Lefevre via Exim-users wrote:
> I've reported the following bug in the Debian BTS[*], as I think that
> spec.txt (from exim 4.93) is incorrect.
>
> In /usr/share/doc/exim4-base/spec.txt.gz :
>
> --------
> In order to append to an NFS file safely from more than one host, it is
> necessary to take out a lock before opening the file, and the lock file
> achieves this. Otherwise, even with fcntl() locking, there is a risk of file
> corruption.

The text goes all the way back to 2002, for Exim 4.0

I've not been able to trace it further. It's possible that
it refers to NFS implementations that were less well-behaved
than current ones.

I do know that NFS was regarded as problematic, as of the '90s.
--
Cheers,
Jeremy