[courier-users] Two issues when deleting maildir folders

[Alain NAKACHE]

Hi All,

Two issues were reported to me concerning folder deletion.

My config :
        - Linux RH 8.0
        - Maildirs are stored on NFS filesystem
        - Courier-Imap 1.7.3
        - MUA : MS  Outlook 2002 / MS Outlook Express 6 / Eudora 5.1.2

First case :

I created this subfolder structure in my INBOX :

+ fold1

  + fold2

    - fold3

When trying to delete fold1, Outlook & Eudora scan subfolders to delete deeper first and so on, while Outlook Express don't and try to delete fold1 first, which is accepted by the imap server leaving the two folders fold2, fold3 in the maildir with a parent folder unknown :

.

..

courierimapsubscribed

courierimapuiddb

cur

.fold1.fold2

.fold1.fold2.fold3

maildirsize

new

tmp

.Trash

I know, Sam, you are not coding glue patches to correct M$ bugs (even if --enable-workarounds-for-imap-client-bugs has been developed :-) ) but I wonder if courier-imap server can refuse folder deletion in case of child folder existence.

Second case :

In very rare case we encounter a problem when deleting a non empty folder with MS Outlook / MS Outlook Express. Remember I use NFS filesharing.

Here is an extract of a chat between MUA and imapd :

...

->      DONE

<-      00X6 OK IDLE completed

->      00XF DELETE "inbox.fold1"

<-      00XF NO Cannot delete this folder.

->      00XG IDLE

<-      entering idle mode

...

After several attempts (its very difficult to obtain)  we have discovered a temporary nfs file named ".nfs0001d02e00000144" in the cur subdirectory while folder deletion, preventing unlink success of this directory. At the end the folder was partially deleted (Maildir/.fold1/cur still exists) which cause an error when the MUA wants to refresh the folders list.

We suspect concurrent imap channel opened by Outlook to send a LIST or similar command while deleting the folder leaving this temporary file which is released when we acknowledge the MS Outlook error dialog.

Before installing version 1.7.3 of courier-imap (1.7.0 was our version for a long time) we never encountered this issue and I wonder if the new folder deletion behaviour which appeared in version 1.7.2 is not responsible of that.

That's all folks.

I'm impatient to have your feedbacks.

Bye.