Re: File locking question

[Carlos Morgado <chbm chbm nu>]

On 2001.07.13 13:38:47 +0100 Olaf Frączyk wrote:
> Hi,
> 
> I use several mailboxes.
> Does Balsa lock (using flock, or fcntl) mailbox files.
> Does this apply to /var/spool/mail/mymailbox only, or to all mailboxes I
> use.
> I would like to know if it is safe to use several Balsas by different
> people with access to the same mailboxes. Does balsa lock file for all time
> it is open, or only for time it writes changes to it?
> 

from the README

Mailbox locking:
---------------
        Balsa uses flock+dotfile for mailbox file locking. It does not
use fcntl (although it can be enabled) since this locking method is
very fragile and often not portable (see for example
http://www.washington.edu/pine/tech-notes/low-level.html#locking).

Make sure that your spool directory has drwxrwxrwt (01777) access
privileges. Presently, dotfile locking requires this unconditionally
In the future, we may relax this requirement and will allow you to
shoot yourself in your leg.


ie, you can --enable-fcntl but you're on your own there :)

> Oh, and addresses, I remember, that it was not safe to update address book
> in the same time by two different balsas. Is it possible now, to share
> address books between users?
> 

humm .. address book = gnomecard. i'm not sure how well gnomecard handles 
multiple readers/writers.

-- 
Carlos Morgado - chbm(at)chbm(dot)nu - http://chbm.nu/ -- gpgkey: 0x1FC57F0A
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