Managing IMAP

Appendix C. IMAP Commands

This appendix covers the IMAP commands as described in RFC 2060 (IMAP4rev1). Commands may only be valid in certain connection states. We’ll list the commands by the state in which they’re valid. Server response codes (untagged responses) are not listed here in detail, but a knowledge of the response codes is not required for general evaluation and trouble-shooting of IMAP sessions. If you require detailed knowledge of the response codes, see Section 7.1 of RFC 2060 (http://www.ietf.org/rfc/rfc2060.txt).

Commands Valid in Any State

CAPABILITY

The CAPABILITY command returns a list of the server’s capabilities (e.g., supported authentication mechanisms and supported IMAP extensions).

Usage

CAPABILITY

Arguments

None

Untagged server response

An untagged CAPABILITY response

Results

OK (command completed successfully)

BAD (invalid arguments or command unknown)

Example

A00001 CAPABILITY
* CAPABILITY IMAP4REV1 MAILBOX-REFERRALS LOGIN-REFERRALS AUTH=CRAM-MD5
A00001 OK Completed

LOGOUT

The LOGOUT command tells the server to close the network connection.

Usage

LOGOUT

Arguments

None

Untagged server responses

An untagged BYE response

Results

OK (logout completed)

BAD (command failed or invalid arguments)

Example

A00003 logout
* BYE localhost IMAP4rev1 server terminating connection
A00003 OK Completed

NOOP

The NOOP command, besides resetting the server’s inactivity autologout timer, also causes a protocol round-trip, which in turn may cause an announcement of new mail. NOOP is often ...