As per Relevance of the word response, we have this rfc below:
Network Working Group M.
Request for Comments: 2061 University of
Category: Informational December 1996
IMAP4 COMPATIBILITY WITH IMAP2
Status of this
This memo provides information for the Internet community. This
does not specify an Internet standard of any kind. Distribution
this memo is unlimited
The Internet Message Access Protocol (IMAP) has been through
revisions and variants in its 10-year history. Many of these
either extinct or extremely rare; in particular, several
variants and the variants described in RFC 1064, RFC 1176, and
1203 fall into this category
One variant, IMAP2bis, is at the time of this writing very common
has been widely distributed with the Pine mailer. Unfortunately
there is no definite document describing IMAP2bis. This document
intended to be read along with RFC 1176 and the most recent IMAP
specification (RFC 2060) to assist implementors in creating an IMAP
implementation to interoperate with implementations that conform
earlier specifications. Nothing in this document is required by
IMAP4 specification; implementors must decide for themselves
they want their implementation to fail if it encounters old software
At the time of this writing, IMAP4 has been updated from the
described in RFC 1730. An implementor who wishes to
with both RFC 1730 and RFC 2060 should refer to both documents
This information is not complete; it reflects current knowledge
server and client implementations as well as "folklore" acquired
the evolution of the protocol. It is NOT a description of how
interoperate with all variants of IMAP, but rather with the
variant that is most likely to be encountered. For
information on interoperating with other old variants, refer to
1732.
IMAP4 client interoperability with IMAP2bis
A quick way to check whether a server implementation supports
IMAP4 specification is to try the CAPABILITY command. An OK
will indicate which variant(s) of IMAP4 are supported by the server
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RFC 2061 IMAP4 Compatibility December 1996
If the client does not find any of its known variant in the response
it should treat the server as IMAP2bis. A BAD response indicates
IMAP2bis or older server
Most IMAP4 facilities are in IMAP2bis. The following
exist
CAPABILITY
The absense of this command indicates IMAP2bis (or older).
AUTHENTICATE command
Use the LOGIN command
LSUB, SUBSCRIBE, and UNSUBSCRIBE
No direct functional equivalent. IMAP2bis had a
called "bboards" which is not in IMAP4. RFC 1176
these with the BBOARD and FIND BBOARDS commands. IMAP2
augmented these with the FIND ALL.BBOARDS, SUBSCRIBE BBOARD
and UNSUBSCRIBE BBOARD commands. It is recommended
none of these commands be implemented in new software
including servers that support old clients
LIST
Use the command FIND ALL.MAILBOXES, which has a similar syn
tax and response to the FIND MAILBOXES command described
RFC 1176. The FIND MAILBOXES command is unlikely to
useful information
* in a
Use the number of messages in the mailbox from the
unsolicited response
SEARCH extensions (character set, additional criteria
Reformulate the search request using only the RFC 1176 syn
tax. This may entail doing multiple searches to achieve
desired results
BODYSTRUCTURE fetch data
Use the non-extensible BODY data item
body sections HEADER, TEXT, MIME, HEADER.FIELDS, HEADER.FIELDS.
Use body section numbers only
BODY.PEEK[section
Use BODY[section] and manually clear the \Seen flag
necessary
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RFC 2061 IMAP4 Compatibility December 1996
FLAGS.SILENT, +FLAGS.SILENT, and -FLAGS.SILENT store data
Use the corresponding non-SILENT versions and ignore
untagged FETCH responses which come back
UID fetch data item and the UID
No functional equivalent
CLOSE
No functional equivalent
In IMAP2bis, the TRYCREATE special information token is sent as
separate unsolicited OK response instead of inside the NO response
IMAP2bis is ambiguous about whether or not flags or internal
are preserved on COPY. It is impossible to know what behavior
supported by the server
IMAP4 server interoperability with IMAP2bis
The only interoperability problem between an IMAP4 server and
well-written IMAP2bis client is an incompatibility with the use
"\" in quoted strings. This is best avoided by using
instead of quoted strings if "\" or <"> is embedded in the string
Security
Security issues are not discussed in this memo
Author's
Mark R.
Networks and Distributed
University of
4545 15th Aveneue
Seattle, WA 98105-4527
Phone: (206) 543-5762
EMail: MRC@CAC.Washington.
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if you see any problems within the linking, don't worry be happy,
this is version 0.1 of the Relevance System and you gotta expect some crappy subroutines sometimes,
just be content we did not write this in Java, which would have made this "bigger and better" HAHAHHA.
RFC documents can be found at I.E.T.F.
Relevance System Copyright © 2002 Spectrum WorldResearch
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collaboration of BobX
