Re: NFS in 2.1.130??

Wayne Schlitt (
02 Dec 1998 10:34:49 -0600

In <> David Luyer <> writes:

> Chip Salzenberg wrote:
> > According to Alan Cox:
> > > procmail style dot locking works over NFS.
> >
> > [...]
> > So does Deliver, if it's compiled with -DHAS_NFS. Unfortunately, the
> > Debian distribution of Deliver isn't. So I recommend that Debian users
> > of Deliver compile it on their own.
> [ ... ] So yes, Debian users should compile their own deliver and/or qpopper
> and/or other mail programs. This is one area Debian is currently lacking -
> there's no "Debian mail locking standard" evident.

I am not a Debian developer, but I do read the mailing lists. I don't
remember how long ago it was, at least 6-9 months ago, maybe longer,
but this subject did come up. I checked the Debian web pages, and I
quickly found Debian Policy Manual, and this relevant web page:

So, if you *do* think that Debian users really need to recompile these
programs to get mail locking working, I am sure that the Debian
developers would appreciate you filing a bug report explaining this
situation. Bug reports can be filed at:

To quote from the Debian Policy Manual:

> 5.5 Mail transport agents
> Debian packages which process electronic mail, whether
> mail-user-agents (MUAs) or mail-transport-agents (MTAs), must make
> sure that they are compatible with the configuration decisions
> below. Failure to do this may result in lost mail, broken From:
> lines, and other serious brain damage!
> [ ... ]
> All Debian MUAs and MTAs have to use the maillock and mailunlock
> functions provided by the liblockfile packages to lock and unlock
> mail boxes. These functions implement a NFS-safe locking
> mechanism. (It is ok if MUAs and MTAs don't link against liblockfile
> but use a compatible mechanism. Please compare the mechanisms very
> carefully!)
> Mailboxes are generally 660 user.mail unless the user has chosen
> otherwise. A MUA may remove a mailbox (unless it has nonstandard
> permissions) in which case the MTA or another MUA must recreate it
> if needed. Mailboxes must be writable by group mail.
> The mail spool is 2775 mail.mail, and MUAs need to be setgid mail to
> do the locking mentioned above (and obviously need to avoid
> accessing other users' mailboxes using this privilege).
> [ more mail stuff deleted... ]

These problems may well have been true for Debian release before 2.0,
and 2.0 did sit as a "development tree" for a long time, but that
doesn't mean that the Debian folks didn't do something about it a long
time ago...


Wayne Schlitt can not assert the truth of all statements in this
article and still be consistent.

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