On Thursday, March 6, 2003, at 02:36 am, Ketil Froyn wrote:
On Thu, 6 Mar 2003, Dale Woolridge wrote:
| I guess time(NULL) is the best we can provide if there is no info on
| former uidvalidity values, but if we know the former value we should add 1
| to it rather than use time(NULL). Or we could wait one second here too
| :-/.
And there's still the case of NFS exported mailbox disks, with multiple
IMAP servers referencing those disks. A reasonable sysadmin would, of
course, ensure the clocks on these machines are synchronized, but it'
s
still a valid example.
You could maybe check the time by touching a file and reading back what time the file was modified, instead of doing time(NULL)? ;)
A neat idea, but perhaps overkill. A sysadmin who doesn't synchronize time among
her servers is going to run into many, many troubles. Furthermore, multiple
IMAP servers isn't necessarily a safe option.
Maildir guarantees safe parallel MTA, *not* MUA operation. In the Maildir/
MUA relationship, the IMAP server(s) is/are the MUA and therefore only one may be guaranteed operating successfully at a time. It is my implicit belief that an IMAP server deals with multiple simultaneous client connections, but multiple separate instances of itself is another issue.
Of course, if the MUA is intelligent about its own locking and concurrency that is fine, but over NFS, there are no guarantees that POSIX locking (i.
e. lockf) operations are supported or even handled by something other than a NOP. Dot-locking is a way to deal with NFS madness, but that has all the problems with it that made Maildir such an elegant solution.
C=)
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If software were really an engineering field, we would learn as engineers
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Caskey <caskey*technocage.com> /// TechnoCage Inc.
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Heuer's Law: Any feature is a bug unless it can be turned off.
