From: Holger K. <hol...@gm...> - 2006-11-07 11:57:59
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Gunter Ohrner schrieb: > I'm currently migrating my mail folder hierachie to a new IMAP server > using mailsync. During the sync mailsync informed me that - as it is also > mentioned in the man page - my drafts do not yet carry a message ID and > thus could not be synced. > > * Can I just safely switch from Message-ID-based message identification to > MD5 for all following syncs? > > * Will mailsync automagically detect the change and rebuild its internal > sync tracking information, or will I have to delete its internal > tracking message? I assume both question get a yes as an answer. But that is only because i never noticed any error when i did so, not insight in the inner workings of mailsync. Could be just coincidence. But as you have your old emails savely stored on the old imap server you should just try and if things fail: delete all emails on the new one and start over. > * Wouldn't it reduce the admittedly small probability of a has collision > if the "Message-ID" header would not be hashed into the MD5 but just > appended? ie. the message identity fingerprint would consist of an MD5 > hash of the "From", "To", "Subject" and "Date" header fields, > concatenated with the "Message-ID" header field. In this case a hash > collision would only misclassify two messages as identical which already > have the same "Message-ID" header, which they normally should not have > in the first place. If they don't have the same Message-ID they can't get the same hash. So no collision anyway. Appending has no advantage over hashing. Just makes comparison uglier. > * Wouldn't it make sense to also hash the message's octet size into the > message identification hash if MD5 is used? > Or may the computable > message size differ slightly depending on the mail store backend? Unfortunately yes. You would need to read the whole mail and count bytes. |