The MessageStore stores a copy of each message in each folder to which it is delivered.¹
Delivery may be directed to a user's INBOX or to any folder in the MessageStore if the folder's IMAP ACL permits posting. A message directed to
user+folder@hostwill be filed into the specified folder named
folder if
the ACL permits; otherwise, it will be delivered to the user's INBOX.
A reserved name is used to deliver to public folders: by default the
name post is used. A message directed to
post+folder@hostwill be delivered to the public folder named
folder if
public posting is enabled; otherwise, the message will be returned to
its originator as undeliverable.
A user's folders and messages are stored in a subdirectory of the directory containing the user's profile file as described in Section 1.3.9 . Public folders are stored in a different directory tree. On UNIX systems, public folders are kept in the directory tree specified by the PMDF_MSGSTORE_MESSAGES option in the PMDF tailor file; on NT systems by the PMDF_MSGSTORE_MESSAGES registy entry; and, on OpenVMS systems in the PMDF_MSGSTORE_MESSAGES: directory tree as specified by the system-wide logical, PMDF_MSGSTORE_MESSAGES.
The IMAP protocol is used to manipulate folders and messages in the MessageStore. A number of IMAP clients provide rich management facilities including ACL and QUOTA support. User management is available through a command line interface, a web-based interface, and a subset of the popstore API as described in Section 2.6 .