On Mon 23 Nov 2020 at 07:24:37 (-0500), rhkra...@gmail.com wrote: > On Monday, November 23, 2020 06:15:09 AM Sven Hartge wrote: > > Joe <j...@jretrading.com> wrote: > > > That's why we have IMAP, which doesn't use mbox. > > > > The IMAP protocal and the backend storage have no connection.
I didn't think this thread was about the backend at all, but about where to place the emails being fetched, and hence the protocol to use. I don't think there's much concern about the final destination of the emails either, but only the immediate destination, ie where emails are placed at the moment of first arrival on the OP's system. > Well, they do in a way -- if you use IMAP from your ISP for example, you > don't > need local storage on your email device (not any of mbox, maildir, or > whatever). > > (I don't use IMAP (I use POP3), but I assume that if I were using IMAP as > described, I could save emails on my local device, but I'm not clear on that > mechanism / storage method.) It may vary by client. With mutt over IMAP, opening a remote INBOX will synchronise the INBOX's headers (only) with a local cache.¹ If and when you read a new message, mutt reads it into a cache where each email is a separate file. That cache is to avoid having to re-transfer the email each time you open it in your INBOX. When you save an email on your computer, it's copied into whichever type of storage you prefer. It might be a mailbox, meaning an mbox or maildir (depending on how you configured it), or just an ordinary file in the filesystem. The main difference between a cached email and one that's been saved to a file or mbox is that the saved one has an extra line (acting as a separator) appended at the start, and a blank line at the end. Two big advantages of IMAP are: . Having looked at the header, you can delete the email without having even transferred the body. . While you read, save, back up, etc, your emails, they're still safely sitting on the server. To truly delete them, you have to flag them as deleted, and then synchronise with the server (ie open a new folder, or close the client, or explicitly synchronise). Repeat, all this is for mutt/IMAP. ¹ Assuming you want a cache. IIRC this first cache is crudely managed, gently growing all the time, and pruned just by deleting it. Cheers, David.
