Arnt Gulbrandsen wrote:
Dave Cridland writes:
The only distinctions in IMAP itself that springs to mind is that
system flags can affect, or be affected by, the IMAP server (\Seen,
\Deleted, \Recent - but not \Answered, \Flagged or \Draft) and that
system flags have shorthand search criteria (ANSWERED, UNSEEN, etc).
Otherwise, they behave identically.
Which reminds me - as I read the imapflags draft, it's not clear
whether \recent can be changed using removeflag (and once removed, set
again using setflag).
I suggest that removeflag should NOT be able to modify \recent, since
similar IMAP commands cannot set it either. hasflag could test it
(since similar IMAP commands can) but considering that the result is
true always, I don't see much value in allowing \recent for hasflag.
I think \recent should be explicitly excluded.
I've added to section 2.1:
Note that it is not possible to use this extension to set or clear the
\Recent flag or any other special system flag which is not settable
in [IMAP]. If the \Recent flag is included in a flag list, it MUST be
silently ignored, but a warning message SHOULD be logged by the Sieve