[comp.mail.elm] Elm 2.1 PL1

oved@techunix.BITNET (Oved Ben-Aroya) (12/20/88)

[]

I was *very* disappointed to see that Elm2.1 PL1 still needs write
permission in the spool mail directory, for a lock file.  Maybe that's
ok for system V, but 4.3 bsd unix uses the flock system call.  If your
system is bsd, you can lose new mail, or the the mailbox may get corrupted:
Elm thinks he can re-write the mbox, and so does sendmail...

I believe that long ago, someone said that he had done the needed work
for bsd.  I was hoping this 'flock' stuff found it's way to the
integrated new Elm version.

--
Dr. Oved Ben-Aroya, Taub Computer Center, Technion City, Haifa 32000, Israel
BITNET: oved at techunix
CSNET and ARPA: oved%techunix.BITNET@cunyvm.cuny.edu
UUCP :  ...psuvax1!techunix.BITNET!oved

syd@dsinc.UUCP (Syd Weinstein) (12/21/88)

In article <6804@techunix.BITNET> techunix!oved@jade.berkeley.edu (Oved Ben-Aroya) writes:
>I was *very* disappointed to see that Elm2.1 PL1 still needs write
>permission in the spool mail directory, for a lock file.  Maybe that's
>ok for system V, but 4.3 bsd unix uses the flock system call.  If your
>system is bsd, you can lose new mail, or the the mailbox may get corrupted:
>Elm thinks he can re-write the mbox, and so does sendmail...

As the Elm Coordinator let me state, no one has submitted patches
for 4.3 compatibility with flock.  If the patches are not submitted
real soon, then they will not make the next version.  For whatever
reason, we had no volunteers from the user community for 'true BSD 4.3'
our BSD type people have Pyramids and Sun's, thus this is 4.2 type BSD.

I would welcome patches that fix the flock problem, but it is a two
fold problem, not just the code to do the flocks, but how do you tell,
at compile time, that you need to use the flock code for mailboxes.
I need to modify the modules used by Configure to determine to set
that flag.  Without both parts, the change is useless.

Volunteers?, send me e-mail.
-- 
=====================================================================
Sydney S. Weinstein, CDP, CCP                   Elm Coordinator
Datacomp Systems, Inc.				Voice: (215) 947-9900
{allegra,bellcore,bpa,vu-vlsi}!dsinc!syd	FAX:   (215) 938-0235

mike@ists.ists.ca (Mike Clarkson) (12/22/88)

In article <6804@techunix.BITNET>, oved@techunix.BITNET (Oved Ben-Aroya) writes:
> I was *very* disappointed to see that Elm2.1 PL1 still needs write
> permission in the spool mail directory, for a lock file.  Maybe that's
> ok for system V, but 4.3 bsd unix uses the flock system call.  If your
> system is bsd, you can lose new mail, or the the mailbox may get corrupted:
> Elm thinks he can re-write the mbox, and so does sendmail...

That depends.

SunOS 3.5 uses lock files and requires write permissions to /usr/spool/mail.
SunOS 4,0 uses network wide locking.

Note that you can make elm sgid daemon and /usr/spool/mail owned by
group deamon to avoid giving elm suid privs on a Sun 3.5 system.

> I believe that long ago, someone said that he had done the needed work
> for bsd.  I was hoping this 'flock' stuff found it's way to the
> integrated new Elm version.

I'm sure it still does!

Mike.


Mike Clarkson					mike@ists.UUCP
Institute for Space and Terrestrial Science	mike@ists.ists.ca
York University, North York, Ontario,		uunet!mnetor!yunexus!ists!mike
CANADA M3J 1P3					+1 (416) 736-5611