Mark Crispin wrote: > Hierarchies can be "hard" (such as UW imapd's export of the UNIX > filesystem) or "soft" (such as Cyrus). > > A hard hierarchy is one in which each level is its own named object. Such > objects may be terminal and/or have other levels of hierachy. Each > non-terminal level contains its subordinate levels. Thus, with > office/secret and office/secret/top, there is an object called "office" > that contains an object called "secret", and "secret" in turn contains an > object called "top". > > A soft hierarchy is basically a non-hierarchical (flat) namespace in which > a particular character is defined by convention to be the delimiter for > "%" in LIST. There is no relationship between office/secret and > office/secret/top other than the first 13 octets being the same. Since > the namespace is basically flat, the terminal vs. other levels of > hierarchy distinction has no meaning; office/secret does not actually > "contain" office/secret/top in any way.
I'm not sure I buy this description of Cyrus. Cyrus *is* hierarchical and office/secret and office/secret/top *are* related -- the latter is a child (directory) of the former. Cyrus exports a filesystem tree just like UW (or INN for Usenet), but it maintains its own database of what directories are actual mailboxes. The presence of a directory doesn't necessarily mean that is a mailbox or can't be used as a mailbox (just like 'comp' isn't a newsgroup). This means that if office/secret/top is DELETEd, Cyrus won't care that the office/secret directory still exists. Apparently UW does care, and this is why office/secret/ would have to be listed by LIST. -- Kenneth Murchison Oceana Matrix Ltd. Software Engineer 21 Princeton Place 716-662-8973 x26 Orchard Park, NY 14127 --PGP Public Key-- http://www.oceana.com/~ken/ksm.pgp
