[Dovecot] Unable to (un)subscribe mbox with AIX, NFS and netapp filer

[Axel Luttgens]

Le 6 juil. 09 à 23:07, Ralf Becker a écrit :

> Hello Axel,
>
> [...]
>
> It's not just the log message. If you have a look on the entire
> function, you'll see that it fails if fchown fails:
>
> [...]

Yes, you're right; I've been too elliptic... :-(
I was worried with a "solution" that potentially could fully hide  
deeper problems, hence the suggestion to at least leave something in  
the logs.


> While this function seems to create all dotlock files (not just for
> the .subscribtions file) this means that on same NFS(4) file systems
> dotlocking is actually not working.

After a quick look, it seems that dotlocking for mbox mailboxes goes  
through another path, and skips that fchmod() operation.
But please don't ask why. ;-)


> The linux man page of chown(3) (in place of fchown(3)) says:
>
> -----------------------------8<--------------------------------
> If owner or group is specified as ( uid_t)-1 or ( gid_t)-1,
> respectively, the corresponding ID of the file shall not be changed.
> If both owner and group are -1, the times need not be updated.
> Upon successful completion, chown() shall mark for update the st_ctime
> field of the file.
> ------------------->8------------------------------------------
>
> Is my understanding of these sentences correct?
> "If owner and group are -1, nothing is done?"
>
> In this case it should be save to skip the call, shouldn't it?

Yes, I guess so.
Unless the rationale for that call is to ensure a correct cache  
flushing for NFS clients, while being some kind of (costly) no-op  
otherwise?
Ahem... Timo?

Axel