Document details about the UWIMAP folder internal data/X-IMAP: thingy.

svn path=/trunk/; revision=4475

diff --git a/transact.c b/transact.c
index a2e8d0b8692ba634e0fdab9271c64870966cff7a..4f5c88e7c6019b599a7ca86ed1763aa3ecd0d617 100644 (file)
--- a/transact.c
+++ b/transact.c
@@ -617,6 +617,29 @@ int readheaders(int sock,
         * on being able to keep base-UID information in a special
         * message at the head of the mailbox.  This message should
         * neither be deleted nor forwarded.
+        *
+        * An example for such a message is (keep this in so people
+        * find it when looking where the special code is to handle the
+        * data):
+        *
+        *   From MAILER-DAEMON Wed Nov 23 11:38:42 2005
+        *   Date: 23 Nov 2005 11:38:42 +0100
+        *   From: Mail System Internal Data <MAILER-DAEMON@mail.example.org>
+        *   Subject: DON'T DELETE THIS MESSAGE -- FOLDER INTERNAL DATA
+        *   Message-ID: <1132742322@mail.example.org>
+        *   X-IMAP: 1132742306 0000000001
+        *   Status: RO
+        *
+        *   This text is part of the internal format of your mail folder, and is not
+        *   a real message.  It is created automatically by the mail system software.
+        *   If deleted, important folder data will be lost, and it will be re-created
+        *   with the data reset to initial values.
+        *
+        * This message is only visible if a POP3 server that is unaware
+        * of these UWIMAP messages is used besides UWIMAP or PINE.
+        *
+        * We will just check if the first message in the mailbox has an
+        * X-IMAP: header.
         */
 #ifdef POP2_ENABLE
        /*