RE: O_SYNC option doesn't work (2.4.18-3)

[Alan Cox]

On Wed, 2002-08-07 at 20:24, Gregory Giguashvili wrote:
> I understand that locking file flushes NFS cache, isn't it? Why can't it be
> flushed by O_SYNC and "sync" options presence? This would make the life much
> easier for programmers...
> 
> This means that we will never be able to drop lockd locking and at the same
> time achieve file consistency via NFS?

Welcome to NFS. You basically need file locking (lockf/posix - flock is
not portably applicable to NFS) and you may need to turn off attribute
caching to make O_APPEND work portably.

Its a pain, but NFS has no other way to infer your transaction
constraints. You need to lock for read and for write on all clients, a
client reading without locking may get stale data.

Personally I use my own little daemons to manage transactional data,
ones that understand my transaction rules