How does folder sharing work in Zimbra, and what permission roles are available?

Folder sharing is done via a SOAP request specifying the target mailbox, folder ID (e.g., `2` for Inbox, `5` for Sent), and permission string. The `perm="r"` grants read-only (Viewer), while `perm="rwidx"` grants read, write, insert, and delete (Manager). You can optionally send a notification email. For more on the API structure, see the Zimbra SOAP API Development Guide.