1 ;;; pop3.el --- Post Office Protocol (RFC 1460) interface
3 ;; Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002
4 ;; Free Software Foundation, Inc.
6 ;; Author: Richard L. Pieri <ratinox@peorth.gweep.net>
7 ;; Daiki Ueno <ueno@ueda.info.waseda.ac.jp>
8 ;; Katsumi Yamaoka <yamaoka@jpl.org>
9 ;; Maintainer: Volunteers
12 ;; This file is part of T-gnus.
14 ;; GNU Emacs is free software; you can redistribute it and/or modify
15 ;; it under the terms of the GNU General Public License as published by
16 ;; the Free Software Foundation; either version 2, or (at your option)
19 ;; GNU Emacs is distributed in the hope that it will be useful,
20 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
21 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 ;; GNU General Public License for more details.
24 ;; You should have received a copy of the GNU General Public License
25 ;; along with GNU Emacs; see the file COPYING. If not, write to the
26 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
27 ;; Boston, MA 02111-1307, USA.
31 ;; Most of the standard Post Office Protocol version 3 (RFC 1460) commands
32 ;; are implemented. The LIST command has not been implemented due to lack
33 ;; of actual usefulness.
34 ;; The optional POP3 command TOP has not been implemented.
36 ;; This program was inspired by Kyle E. Jones's vm-pop program.
40 (eval-when-compile (require 'cl))
44 (defvar pop3-maildrop (or (user-login-name) (getenv "LOGNAME") (getenv "USER") nil)
46 (defvar pop3-mailhost (or (getenv "MAILHOST") nil)
50 (defvar pop3-connection-type nil
51 "*POP3 connection type.")
53 (defvar pop3-password-required t
54 "*Non-nil if a password is required when connecting to POP server.")
55 (defvar pop3-password nil
56 "*Password to use when connecting to POP server.")
58 (defvar pop3-authentication-scheme 'pass
59 "*POP3 authentication scheme.
60 Defaults to 'pass, for the standard USER/PASS authentication. Other valid
63 (defvar pop3-timestamp nil
64 "Timestamp returned when initially connected to the POP server.
65 Used for APOP authentication.")
67 (defvar pop3-leave-mail-on-server nil
68 "Non-nil if mail is to be left on the server and UIDL used for message retrieval.")
70 (defvar pop3-maximum-message-size nil
71 "If non-nil only download messages smaller than this.")
73 (defvar pop3-except-header-regexp nil
74 "If non-nil we do not retrieve messages whose headers are matching this regexp.")
76 (defvar pop3-uidl-file-name "~/.uidls"
77 "File in which to store the UIDL of processed messages.")
79 (defvar pop3-uidl-support 'dont-know
80 "Whether the server supports UIDL.
81 Nil means no, t means yes, not-nil-or-t means yet to be determined.")
83 (defvar pop3-uidl-obarray (make-vector 31 0)
86 (defvar pop3-read-point nil)
87 (defvar pop3-debug nil)
90 (autoload 'open-ssl-stream "ssl")
91 (autoload 'starttls-open-stream "starttls")
92 (autoload 'starttls-negotiate "starttls"))
94 (defvar pop3-ssl-program-name
95 (if (exec-installed-p "openssl")
98 "The program to run in a subprocess to open an SSL connection.")
100 (defvar pop3-ssl-program-arguments
101 '("s_client" "-quiet")
102 "Arguments to be passed to the program `pop3-ssl-program-name'.")
104 (defun pop3-progress-message (format percent &rest args)
105 (apply (function message) format args))
107 (defun pop3-movemail (&optional crashbox)
108 "Transfer contents of a maildrop to the specified CRASHBOX."
109 (or crashbox (setq crashbox (expand-file-name "~/.crashbox")))
110 (let* ((process (pop3-open-server pop3-mailhost pop3-port))
111 (crashbuf (get-buffer-create " *pop3-retr*"))
114 (pop3-password pop3-password)
115 (pop3-uidl-file-name (convert-standard-filename
116 (concat pop3-uidl-file-name "-"
118 retrieved-messages messages)
119 ;; for debugging only
120 (if pop3-debug (switch-to-buffer (process-buffer process)))
121 ;; query for password
122 (if (and pop3-password-required (not pop3-password))
124 (pop3-read-passwd (format "Password for %s: " pop3-maildrop))))
125 (cond ((equal 'apop pop3-authentication-scheme)
126 (pop3-apop process pop3-maildrop))
127 ((equal 'pass pop3-authentication-scheme)
128 (pop3-user process pop3-maildrop)
130 (t (error "Invalid POP3 authentication scheme")))
131 ;; get messages that are suitable for download
132 (message "Retrieving message list...")
133 (setq messages (pop3-get-message-numbers process)
134 message-count (length (cdr messages)))
135 (message "Retrieving message list...%d of %d unread"
136 message-count (pop messages))
138 (unless (not (stringp crashbox))
140 (pop3-progress-message
141 "Retrieving message %d of %d (%d octets) from %s..."
142 (floor (* (/ (float n) message-count) 100))
143 n message-count (cdar messages) pop3-mailhost)
144 (pop3-retr process (caar messages) crashbuf)
145 (push (caar messages) retrieved-messages)
146 (setq messages (cdr messages)
148 (with-current-buffer crashbuf
149 (write-region-as-binary (point-min) (point-max)
150 crashbox 'append 'nomesg))
151 ;; mark messages as read
152 (when pop3-leave-mail-on-server
154 ;; now delete the messages we have retrieved
155 (unless pop3-leave-mail-on-server
156 (dolist (n retrieved-messages)
157 (message "Deleting message %d of %d from %s..."
158 n message-count pop3-mailhost)
159 (pop3-dele process n)))
162 (kill-buffer crashbuf)
165 (defun pop3-get-message-count ()
166 "Return the number of messages in the maildrop."
167 (let* ((process (pop3-open-server pop3-mailhost pop3-port))
169 (pop3-password pop3-password)
171 ;; for debugging only
172 (if pop3-debug (switch-to-buffer (process-buffer process)))
173 ;; query for password
174 (if (and pop3-password-required (not pop3-password))
176 (pop3-read-passwd (format "Password for %s: " pop3-maildrop))))
177 (cond ((equal 'apop pop3-authentication-scheme)
178 (pop3-apop process pop3-maildrop))
179 ((equal 'pass pop3-authentication-scheme)
180 (pop3-user process pop3-maildrop)
182 (t (error "Invalid POP3 authentication scheme")))
183 (setq message-count (car (pop3-stat process)))
187 (defun pop3-open-server (mailhost port)
188 "Open TCP connection to MAILHOST on PORT.
189 Returns the process associated with the connection.
190 Argument PORT specifies connecting port."
193 (set-buffer (get-buffer-create (concat " trace of POP session to "
196 (setq pop3-read-point (point-min))
200 ((eq pop3-connection-type 'ssl)
201 (pop3-open-ssl-stream "POP" (current-buffer) mailhost port))
202 ((eq pop3-connection-type 'tls)
203 (pop3-open-tls-stream "POP" (current-buffer) mailhost port))
205 (open-network-stream-as-binary "POP" (current-buffer)
207 (let ((response (pop3-read-response process t)))
209 (substring response (or (string-match "<" response) 0)
210 (+ 1 (or (string-match ">" response) -1)))))
213 (defun pop3-open-ssl-stream-1 (name buffer host service extra-arg)
215 (let* ((ssl-program-name
216 pop3-ssl-program-name)
217 (ssl-program-arguments
218 `(,@pop3-ssl-program-arguments
220 "-connect" ,(format "%s:%d" host service)))
221 (process (open-ssl-stream name buffer host service)))
223 (with-current-buffer buffer
224 (goto-char (point-min))
225 (while (and (memq (process-status process) '(open run))
226 (goto-char (point-max))
228 (not (looking-at "+OK")))
229 (accept-process-output process 1)
231 (delete-region (point-min) (point)))
232 (and process (memq (process-status process) '(open run))
235 (defun pop3-open-ssl-stream (name buffer host service)
236 "Open a SSL connection for a service to a host.
237 Returns a subprocess-object to represent the connection.
238 Args are NAME BUFFER HOST SERVICE."
239 (cond ((eq system-type 'windows-nt)
240 (let (selective-display
241 (coding-system-for-write 'binary)
242 (coding-system-for-read 'raw-text-dos))
243 (or (pop3-open-ssl-stream-1 name buffer host service "-ssl3")
244 (pop3-open-ssl-stream-1 name buffer host service "-ssl2"))))
247 (or (pop3-open-ssl-stream-1 name buffer host service "-ssl3")
248 (pop3-open-ssl-stream-1 name buffer host service "-ssl2"))))))
250 (defun pop3-open-tls-stream (name buffer host service)
251 "Open a TLSv1 connection for a service to a host.
252 Returns a subprocess-object to represent the connection.
253 Args are NAME BUFFER HOST SERVICE."
255 (as-binary-process (starttls-open-stream
256 name buffer host service))))
258 (starttls-negotiate process)
263 (defun pop3-process-filter (process output)
265 (set-buffer (process-buffer process))
266 (goto-char (point-max))
269 (defun pop3-send-command (process command)
270 (set-buffer (process-buffer process))
271 (goto-char (point-max))
272 ;; (if (= (aref command 0) ?P)
273 ;; (insert "PASS <omitted>\r\n")
274 ;; (insert command "\r\n"))
275 (setq pop3-read-point (point))
276 (goto-char (point-max))
277 (process-send-string process (concat command "\r\n"))
280 (defun pop3-read-response (process &optional return)
281 "Read the response from the server PROCESS.
282 Return the response string if optional second argument RETURN is non-nil."
283 (let ((case-fold-search nil)
286 (set-buffer (process-buffer process))
287 (goto-char pop3-read-point)
288 (while (not (search-forward "\r\n" nil t))
289 (accept-process-output process 3)
290 (goto-char pop3-read-point))
291 (setq match-end (point))
292 (goto-char pop3-read-point)
293 (if (looking-at "-ERR")
294 (error (buffer-substring (point) (- match-end 2)))
295 (if (not (looking-at "+OK"))
296 (progn (setq pop3-read-point match-end) nil)
297 (setq pop3-read-point match-end)
299 (buffer-substring (point) match-end)
303 (defvar pop3-read-passwd nil)
304 (defun pop3-read-passwd (prompt)
305 (if (not pop3-read-passwd)
306 (if (fboundp 'read-passwd)
307 (setq pop3-read-passwd 'read-passwd)
308 (if (load "passwd" t)
309 (setq pop3-read-passwd 'read-passwd)
310 (autoload 'ange-ftp-read-passwd "ange-ftp")
311 (setq pop3-read-passwd 'ange-ftp-read-passwd))))
312 (funcall pop3-read-passwd prompt))
314 (defun pop3-clean-region (start end)
315 (setq end (set-marker (make-marker) end))
318 (while (and (< (point) end) (search-forward "\r\n" end t))
319 (replace-match "\n" t t))
321 (while (re-search-forward "\n\n\\(From \\)" end t)
322 (replace-match "\n\n>\\1" t nil))
324 (while (and (< (point) end) (re-search-forward "^\\." end t))
325 (replace-match "" t t)
327 (set-marker end nil))
329 (eval-when-compile (defvar parse-time-months))
331 ;; Copied from message-make-date.
332 (defun pop3-make-date (&optional now)
333 "Make a valid date header.
334 If NOW, use that time instead."
335 (require 'parse-time)
336 (let* ((now (or now (current-time)))
337 (zone (nth 8 (decode-time now)))
341 (setq zone (- zone)))
343 (format-time-string "%d" now)
344 ;; The month name of the %b spec is locale-specific. Pfff.
346 (capitalize (car (rassoc (nth 4 (decode-time now))
347 parse-time-months))))
348 (format-time-string "%Y %H:%M:%S " now)
349 ;; We do all of this because XEmacs doesn't have the %z spec.
350 (format "%s%02d%02d" sign (/ zone 3600) (/ (% zone 3600) 60)))))
352 (defun pop3-munge-message-separator (start end)
353 "Check to see if a message separator exists. If not, generate one."
356 (narrow-to-region start end)
357 (goto-char (point-min))
358 (if (not (or (looking-at "From .?") ; Unix mail
359 (looking-at "\001\001\001\001\n") ; MMDF
360 (looking-at "BABYL OPTIONS:") ; Babyl
362 (let* ((from (mail-strip-quoted-names (mail-fetch-field "From")))
363 (tdate (mail-fetch-field "Date"))
364 (date (split-string (or (and tdate
365 (not (string= "" tdate))
370 ;; sample date formats I have seen
371 ;; Date: Tue, 9 Jul 1996 09:04:21 -0400 (EDT)
372 ;; Date: 08 Jul 1996 23:22:24 -0400
374 ;; Tue Jul 9 09:04:21 1996
377 "Tue Jan 1 00:00:0 1900")
378 ((string-match "[A-Z]" (nth 0 date))
379 (format "%s %s %s %s %s"
380 (nth 0 date) (nth 2 date) (nth 1 date)
381 (nth 4 date) (nth 3 date)))
383 ;; this really needs to be better but I don't feel
384 ;; like writing a date to day converter.
385 (format "Sun %s %s %s %s"
386 (nth 1 date) (nth 0 date)
387 (nth 3 date) (nth 2 date)))
389 (setq From_ (format "\nFrom %s %s\n" from date))
390 (while (string-match "," From_)
391 (setq From_ (concat (substring From_ 0 (match-beginning 0))
392 (substring From_ (match-end 0)))))
393 (goto-char (point-min))
395 (if (search-forward "\n\n" nil t)
397 (goto-char (point-max))
399 (narrow-to-region (point) (point-max))
400 (let ((size (- (point-max) (point-min))))
401 (goto-char (point-min))
404 (insert (format "Content-Length: %s\n" size)))
409 (defun pop3-get-message-numbers (process)
410 "Get the list of message numbers and lengths to retrieve via PROCESS."
411 ;; we use the LIST comand first anyway to get the message lengths.
412 ;; then if we're leaving mail on the server, see if the UIDL command
413 ;; is implemented. if so, we use it to get the message number list.
414 (let* ((messages (pop3-list process))
415 (total (or (pop messages) 0))
416 (uidl (if pop3-leave-mail-on-server
417 (pop3-get-uidl process)))
420 ;; only retrieve messages matching our regexp or in the uidl list
422 ;; remove elements not in the uidl, this assumes the uidl is short
423 (or (not (eq pop3-uidl-support t))
424 (memq (caar messages) uidl))
426 ;; don't download messages that are too large
427 (not (and pop3-maximum-message-size
428 (> (cdar messages) pop3-maximum-message-size)))
429 (not (and pop3-except-header-regexp
430 (string-match pop3-except-header-regexp
431 (pop3-top process (caar messages) 0)))))
432 (push (car messages) out))
433 (setq messages (cdr messages)))
434 (cons total (reverse out))))
436 (defun pop3-get-uidl (process)
437 "Use PROCESS to get a list of unread message numbers."
438 (let ((messages (pop3-uidl process)) uidl)
439 (if (or (null messages) (null pop3-uidl-support))
440 (setq pop3-uidl-support nil)
441 (setq pop3-uidl-support t)
444 (when (file-readable-p pop3-uidl-file-name)
445 (insert-file-contents pop3-uidl-file-name))
446 (goto-char (point-min))
447 (while (looking-at "\\([^ \n\t]+\\)")
448 (set (intern (match-string 1) pop3-uidl-obarray)
452 (dolist (message (cdr messages))
453 (if (setq uidl (intern-soft (cdr message) pop3-uidl-obarray))
454 (setcar (symbol-value uidl) (car message))
455 (set (intern (cdr message) pop3-uidl-obarray)
456 (cons (car message) nil))))
457 (pop3-get-unread-message-numbers))
460 (defun pop3-get-unread-message-numbers ()
461 "Return a sorted list of unread msg numbers to retrieve."
463 (mapatoms (lambda (atom)
464 (if (not (cdr (symbol-value atom)))
465 (push (car (symbol-value atom)) nums)))
469 (defun pop3-save-uidls ()
470 "Save the updated UIDLs to disk for use next time."
471 (when (and pop3-leave-mail-on-server
472 ;; UIDL hash table is non-empty
473 (let ((len (length pop3-uidl-obarray)))
475 (setq len (if (symbolp (aref pop3-uidl-obarray (1- len)))
478 (when (file-readable-p pop3-uidl-file-name)
479 (copy-file pop3-uidl-file-name
480 (concat pop3-uidl-file-name ".old")
481 'overwrite 'keeptime))
483 (with-temp-file pop3-uidl-file-name
486 (when (car (symbol-value atom))
487 (insert (format "%s\n" atom))))
489 (fillarray pop3-uidl-obarray 0)))
494 ;; AUTHORIZATION STATE
496 (defun pop3-user (process user)
497 "Send USER information to POP3 server."
498 (pop3-send-command process (format "USER %s" user))
499 (let ((response (pop3-read-response process t)))
500 (if (not (and response (string-match "+OK" response)))
501 (error (format "USER %s not valid" user)))))
503 (defun pop3-pass (process)
504 "Send authentication information to the server."
505 (pop3-send-command process (format "PASS %s" pop3-password))
506 (let ((response (pop3-read-response process t)))
507 (if (not (and response (string-match "+OK" response)))
508 (pop3-quit process))))
510 ;; When this file is being compiled in the Gnus (not T-gnus) source
511 ;; tree, `md5' might have been defined in w3/md5.el, ./lpath.el or one
512 ;; of some other libraries and `md5' will accept only 3 arguments. We
513 ;; will deceive the byte-compiler not to say warnings.
515 (if (fboundp 'eval-when)
516 ;; `eval-when' might not be provided when loading .el file.
518 (let ((def (assq 'md5 byte-compile-function-environment)))
520 (setcdr def '(lambda (object &optional start end
521 coding-system noerror)))
522 (setq byte-compile-function-environment
523 (cons '(md5 . (lambda (object &optional start end
524 coding-system noerror)))
525 byte-compile-function-environment)))))))
527 ;; Note that `pop3-md5' should never encode a given string to use for
528 ;; the apop authentication.
531 (if (condition-case nil
533 Check whether the 4th argument CODING-SYSTEM is allowed"
536 ;; Emacs 21 or XEmacs 21
537 ;; (md5 OBJECT &optional START END CODING-SYSTEM NOERROR)
538 (defun pop3-md5 (string)
539 (md5 string nil nil 'binary))
540 ;; The reason why the program reaches here:
541 ;; 1. XEmacs 20 is running and the built-in `md5' doesn't
542 ;; allow the 4th argument.
543 ;; 2. `md5' has been defined by one of some lisp libraries.
544 ;; 3. This file is being compiled in the Gnus source tree,
545 ;; and `md5' has been defined in lpath.el.
546 (defalias 'pop3-md5 'md5))
547 ;; The lisp function will be provided by FLIM or other libraries.
548 (autoload 'md5 "md5")
549 (defalias 'pop3-md5 'md5)))
551 (defun pop3-apop (process user)
552 "Send alternate authentication information to the server."
553 (let ((pass pop3-password))
554 (if (and pop3-password-required (not pass))
556 (pop3-read-passwd (format "Password for %s: " pop3-maildrop))))
558 (let ((hash (pop3-md5 (concat pop3-timestamp pass))))
559 (pop3-send-command process (format "APOP %s %s" user hash))
560 (let ((response (pop3-read-response process t)))
561 (if (not (and response (string-match "+OK" response)))
562 (pop3-quit process)))))
565 (defun pop3-stls (process)
566 "Query whether TLS extension is supported"
567 (pop3-send-command process "STLS")
568 (let ((response (pop3-read-response process t)))
569 (if (not (and response (string-match "+OK" response)))
570 (pop3-quit process))))
574 (defun pop3-stat (process)
575 "Return the number of messages in the maildrop and the maildrop's size."
576 (pop3-send-command process "STAT")
577 (let ((response (pop3-read-response process t)))
578 (list (string-to-int (nth 1 (split-string response " ")))
579 (string-to-int (nth 2 (split-string response " "))))
582 (defun pop3-retr (process msg crashbuf)
583 "Retrieve message-id MSG to buffer CRASHBUF."
584 (pop3-send-command process (format "RETR %s" msg))
585 (pop3-read-response process)
587 (let ((region (pop3-get-extended-response process)))
588 (pop3-munge-message-separator (car region) (cadr region))
589 (append-to-buffer crashbuf (car region) (cadr region))
590 (delete-region (car region) (cadr region))
593 (defun pop3-dele (process msg)
594 "Mark message-id MSG as deleted."
595 (pop3-send-command process (format "DELE %s" msg))
596 (pop3-read-response process))
598 (defun pop3-noop (process msg)
600 (pop3-send-command process "NOOP")
601 (pop3-read-response process))
603 (defun pop3-last (process)
604 "Return highest accessed message-id number for the session."
605 (pop3-send-command process "LAST")
606 (let ((response (pop3-read-response process t)))
607 (string-to-int (nth 1 (split-string response " ")))
610 (defun pop3-rset (process)
611 "Remove all delete marks from current maildrop."
612 (pop3-send-command process "RSET")
613 (pop3-read-response process))
617 (defun pop3-quit (process)
618 "Close connection to POP3 server.
619 Tell server to remove all messages marked as deleted, unlock the maildrop,
620 and close the connection."
621 (pop3-send-command process "QUIT")
622 (pop3-read-response process t)
625 (set-buffer (process-buffer process))
626 (goto-char (point-max))
627 (delete-process process))))
629 (defun pop3-uidl (process &optional msgno)
630 "Return the results of a UIDL command in PROCESS for optional MSGNO.
631 If UIDL is unsupported on this mail server or if msgno is invalid, return nil.
632 Otherwise, return a list in the form
634 (N (1 UIDL-1) (2 UIDL-2) ... (N UIDL-N))
638 N is an integer for the number of UIDLs returned (could be 0)
642 (pop3-send-command process (format "UIDL %d" msgno))
643 (pop3-send-command process "UIDL"))
645 (if (null (pop3-read-response process t))
646 nil ;; UIDL is not supported on this server
650 (apply 'narrow-to-region (pop3-get-extended-response process))
651 (goto-char (point-min))
652 (while (looking-at "\\([^ \n\t]*\\) \\([^ \n\t]*\\)")
653 (setq msgno (string-to-int (match-string 1))
654 uidl (match-string 2))
655 (push (cons msgno uidl) pairs)
656 (beginning-of-line 2))
657 (cons (length pairs) (nreverse pairs))
660 (defun pop3-list (process &optional msgno)
661 "Return the results of a LIST command for PROCESS and optional MSGNO.
662 If (optional) msgno is invalid, return nil. Otherwise, return a list
665 (N (1 LEN-1) (2 LEN-2) ... (N LEN-N))
669 N is an integer for the number of msg/len pairs (could be 0)
670 LEN-n is an integer."
672 (pop3-send-command process (format "LIST %d" msgno))
673 (pop3-send-command process "LIST"))
675 (if (null (pop3-read-response process t))
676 nil ;; MSGNO is not valid number
680 (apply 'narrow-to-region (pop3-get-extended-response process))
681 (goto-char (point-min))
682 (while (looking-at "\\([^ \n\t]*\\) \\([^ \n\t]*\\)")
683 (setq msgno (string-to-int (match-string 1))
684 len (string-to-int (match-string 2)))
685 (push (cons msgno len) pairs)
686 (beginning-of-line 2))
687 (cons (length pairs) (nreverse pairs))
690 (defun pop3-top (process msgno &optional lines)
691 "Return the top LINES of messages for PROCESS and MSGNO.
692 If msgno is invalid, return nil. Otherwise, return a string."
693 (pop3-send-command process (format "TOP %d %d" msgno (or lines 1)))
694 (if (pop3-read-response process t)
695 nil ;; MSGNO is not valid number
697 (apply 'buffer-substring (pop3-get-extended-response process)))
702 (defun pop3-get-extended-response (process)
703 "Get the extended pop3 response in the PROCESS buffer."
704 (let ((start pop3-read-point) end)
705 (set-buffer (process-buffer process))
707 (while (not (re-search-forward "^\\.\r\n" nil t))
708 (accept-process-output process 3)
710 (setq pop3-read-point (point-marker))
711 (goto-char (match-beginning 0))
712 (setq end (point-marker))
713 (pop3-clean-region start end)
717 ;; Summary of POP3 (Post Office Protocol version 3) commands and responses
719 ;;; AUTHORIZATION STATE
721 ;; Initial TCP connection
723 ;; Restrictions: none
724 ;; Possible responses:
725 ;; +OK [POP3 server ready]
728 ;; Arguments: a server specific user-id (required)
729 ;; Restrictions: authorization state [after unsuccessful USER or PASS
730 ;; Possible responses:
731 ;; +OK [valid user-id]
732 ;; -ERR [invalid user-id]
735 ;; Arguments: a server/user-id specific password (required)
736 ;; Restrictions: authorization state, after successful USER
737 ;; Possible responses:
738 ;; +OK [maildrop locked and ready]
739 ;; -ERR [invalid password]
740 ;; -ERR [unable to lock maildrop]
744 ;; Restrictions: authorization state
745 ;; Possible responses:
746 ;; +OK [negotiation is ready]
747 ;; -ERR [security layer is already active]
749 ;;; TRANSACTION STATE
753 ;; Restrictions: transaction state
754 ;; Possible responses:
755 ;; +OK nn mm [# of messages, size of maildrop]
758 ;; Arguments: a message-id (optional)
759 ;; Restrictions: transaction state; msg must not be deleted
760 ;; Possible responses:
761 ;; +OK [scan listing follows]
762 ;; -ERR [no such message]
765 ;; Arguments: a message-id (required), number of lines (optional)
766 ;; Restrictions: transaction state; msg must not be deleted
767 ;; Possible responses:
768 ;; +OK [partial message listing follows]
769 ;; -ERR [no such message]
772 ;; Arguments: a message-id (optional)
773 ;; Restrictions: transaction state; msg must not be deleted
774 ;; Possible responses:
775 ;; +OK [uidl listing follows]
776 ;; -ERR [no such message]
779 ;; Arguments: a message-id (required)
780 ;; Restrictions: transaction state; msg must not be deleted
781 ;; Possible responses:
782 ;; +OK [message contents follow]
783 ;; -ERR [no such message]
786 ;; Arguments: a message-id (required)
787 ;; Restrictions: transaction state; msg must not be deleted
788 ;; Possible responses:
789 ;; +OK [message deleted]
790 ;; -ERR [no such message]
794 ;; Restrictions: transaction state
795 ;; Possible responses:
800 ;; Restrictions: transaction state
801 ;; Possible responses:
802 ;; +OK nn [highest numbered message accessed]
806 ;; Restrictions: transaction state
807 ;; Possible responses:
808 ;; +OK [all delete marks removed]
814 ;; Restrictions: none
815 ;; Possible responses:
816 ;; +OK [TCP connection closed]
820 ;;; pop3.el ends here