Justin Vallon <vallon(a)mindspring.com> writes:
> On 7 Nov 1998, SL Baur wrote:
>
> > Justin Vallon <vallon(a)mindspring.com> writes in xemacs-beta(a)xemacs.org:
> >
> > > I seem to remember somewhere that NFS writes may be postponed until
> > > close().
> >
> > This brings back bad memories of old flame wars. I don't think NFS
> > will do this, but I know AFS can raise errors on close. If Dejanews
> > has restored enough old netnews, there should be megabytes on this
> > topic in the old archives.
> >
(snip)
>
> HP/UX 10.20, man close:
>
> ERRORS
> close() fails if the any of following conditions are encountered:
>
> ...
>
> [ENOSPC] Not enough space on the file system. This error
> can occur when closing a file on an NFS file
> system. [When a write() system call is executed
> on a local file system and if a new buffer needs
> to be allocated to hold the data, the buffer is
> mapped onto the disk at that time. A full disk is
> detected at this time and write() returns an
> error. When the write() system call is executed
> on an NFS file system, the new buffer is allocated
> without communicating with the NFS server to see
> if there is space for the buffer (to improve NFS
> performance). It is only when the buffer is
> written to the server (at file close or the buffer
> is full) that the disk-full condition is
> detected.]
>
> So, it appears that at least the HP NFS write() call can be cached and the
> cache is not write-through. Hence, a flush would most likely be required,
> or else stat() may be using a stale last-modify time.
The NFS server on VOS used to do something worse. After the close,
the modtime of the file would change slowly for about 20 seconds, then
settle to a stable value. My solution was to edit using ange-ftp
instead of NFS, as it was not only more reliable but also faster. The
VOS NFS server was a piece of junk.
It may still be, but I haven't had occasion to use it for about 3
years.
Darron Shaffer