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a1720df0 | 3 | @setfilename ../info/emacs-mime |
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4 | @settitle Emacs MIME Manual |
5 | @synindex fn cp | |
6 | @synindex vr cp | |
7 | @synindex pg cp | |
dd8839b0 | 8 | |
18f952d5 | 9 | @copying |
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10 | This file documents the Emacs MIME interface functionality. |
11 | ||
b223e22d | 12 | Copyright @copyright{} 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, |
4e6835db | 13 | 2006, 2007 Free Software Foundation, Inc. |
dd8839b0 | 14 | |
18f952d5 | 15 | @quotation |
dd8839b0 | 16 | Permission is granted to copy, distribute and/or modify this document |
678e7c71 | 17 | under the terms of the GNU Free Documentation License, Version 1.2 or |
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18 | any later version published by the Free Software Foundation; with no |
19 | Invariant Sections, with the Front-Cover texts being ``A GNU | |
23f87bed | 20 | Manual'', and with the Back-Cover Texts as in (a) below. A copy of the |
dd8839b0 | 21 | license is included in the section entitled ``GNU Free Documentation |
2482f038 | 22 | License'' in the Emacs manual. |
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23 | |
24 | (a) The FSF's Back-Cover Text is: ``You have freedom to copy and modify | |
25 | this GNU Manual, like GNU software. Copies published by the Free | |
26 | Software Foundation raise funds for GNU development.'' | |
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27 | |
28 | This document is part of a collection distributed under the GNU Free | |
29 | Documentation License. If you want to distribute this document | |
30 | separately from the collection, you can do so by adding a copy of the | |
31 | license to the document, as described in section 6 of the license. | |
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32 | @end quotation |
33 | @end copying | |
dd8839b0 | 34 | |
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35 | @dircategory Emacs |
36 | @direntry | |
23f87bed | 37 | * Emacs MIME: (emacs-mime). Emacs MIME de/composition library. |
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38 | @end direntry |
39 | @iftex | |
40 | @finalout | |
41 | @end iftex | |
42 | @setchapternewpage odd | |
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43 | |
44 | @titlepage | |
45 | @title Emacs MIME Manual | |
46 | ||
47 | @author by Lars Magne Ingebrigtsen | |
48 | @page | |
dd8839b0 | 49 | @vskip 0pt plus 1filll |
18f952d5 | 50 | @insertcopying |
dd8839b0 | 51 | @end titlepage |
dd8839b0 | 52 | |
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53 | @node Top |
54 | @top Emacs MIME | |
55 | ||
56 | This manual documents the libraries used to compose and display | |
57 | @acronym{MIME} messages. | |
58 | ||
3d80e1a2 | 59 | This manual is directed at users who want to modify the behavior of |
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60 | the @acronym{MIME} encoding/decoding process or want a more detailed |
61 | picture of how the Emacs @acronym{MIME} library works, and people who want | |
62 | to write functions and commands that manipulate @acronym{MIME} elements. | |
63 | ||
64 | @acronym{MIME} is short for @dfn{Multipurpose Internet Mail Extensions}. | |
65 | This standard is documented in a number of RFCs; mainly RFC2045 (Format | |
66 | of Internet Message Bodies), RFC2046 (Media Types), RFC2047 (Message | |
67 | Header Extensions for Non-@acronym{ASCII} Text), RFC2048 (Registration | |
68 | Procedures), RFC2049 (Conformance Criteria and Examples). It is highly | |
69 | recommended that anyone who intends writing @acronym{MIME}-compliant software | |
70 | read at least RFC2045 and RFC2047. | |
71 | ||
72 | @menu | |
73 | * Decoding and Viewing:: A framework for decoding and viewing. | |
74 | * Composing:: @acronym{MML}; a language for describing @acronym{MIME} parts. | |
75 | * Interface Functions:: An abstraction over the basic functions. | |
76 | * Basic Functions:: Utility and basic parsing functions. | |
77 | * Standards:: A summary of RFCs and working documents used. | |
78 | * Index:: Function and variable index. | |
79 | @end menu | |
80 | ||
81 | ||
82 | @node Decoding and Viewing | |
83 | @chapter Decoding and Viewing | |
84 | ||
85 | This chapter deals with decoding and viewing @acronym{MIME} messages on a | |
86 | higher level. | |
87 | ||
88 | The main idea is to first analyze a @acronym{MIME} article, and then allow | |
89 | other programs to do things based on the list of @dfn{handles} that are | |
90 | returned as a result of this analysis. | |
91 | ||
92 | @menu | |
93 | * Dissection:: Analyzing a @acronym{MIME} message. | |
94 | * Non-MIME:: Analyzing a non-@acronym{MIME} message. | |
95 | * Handles:: Handle manipulations. | |
96 | * Display:: Displaying handles. | |
97 | * Display Customization:: Variables that affect display. | |
98 | * Files and Directories:: Saving and naming attachments. | |
99 | * New Viewers:: How to write your own viewers. | |
100 | @end menu | |
101 | ||
102 | ||
103 | @node Dissection | |
104 | @section Dissection | |
105 | ||
106 | The @code{mm-dissect-buffer} is the function responsible for dissecting | |
107 | a @acronym{MIME} article. If given a multipart message, it will recursively | |
108 | descend the message, following the structure, and return a tree of | |
109 | @acronym{MIME} handles that describes the structure of the message. | |
110 | ||
111 | @node Non-MIME | |
112 | @section Non-MIME | |
113 | @vindex mm-uu-configure-list | |
114 | ||
115 | Gnus also understands some non-@acronym{MIME} attachments, such as | |
116 | postscript, uuencode, binhex, yenc, shar, forward, gnatsweb, pgp, | |
117 | diff. Each of these features can be disabled by add an item into | |
118 | @code{mm-uu-configure-list}. For example, | |
119 | ||
120 | @lisp | |
121 | (require 'mm-uu) | |
122 | (add-to-list 'mm-uu-configure-list '(pgp-signed . disabled)) | |
123 | @end lisp | |
124 | ||
125 | @table @code | |
126 | @item postscript | |
127 | @findex postscript | |
128 | Postscript file. | |
129 | ||
130 | @item uu | |
131 | @findex uu | |
132 | Uuencoded file. | |
133 | ||
134 | @item binhex | |
135 | @findex binhex | |
136 | Binhex encoded file. | |
137 | ||
138 | @item yenc | |
139 | @findex yenc | |
140 | Yenc encoded file. | |
141 | ||
142 | @item shar | |
143 | @findex shar | |
144 | Shar archive file. | |
145 | ||
146 | @item forward | |
147 | @findex forward | |
148 | Non-@acronym{MIME} forwarded message. | |
149 | ||
150 | @item gnatsweb | |
151 | @findex gnatsweb | |
152 | Gnatsweb attachment. | |
153 | ||
154 | @item pgp-signed | |
155 | @findex pgp-signed | |
156 | @acronym{PGP} signed clear text. | |
157 | ||
158 | @item pgp-encrypted | |
159 | @findex pgp-encrypted | |
160 | @acronym{PGP} encrypted clear text. | |
161 | ||
162 | @item pgp-key | |
163 | @findex pgp-key | |
164 | @acronym{PGP} public keys. | |
165 | ||
166 | @item emacs-sources | |
167 | @findex emacs-sources | |
168 | @vindex mm-uu-emacs-sources-regexp | |
169 | Emacs source code. This item works only in the groups matching | |
170 | @code{mm-uu-emacs-sources-regexp}. | |
171 | ||
172 | @item diff | |
173 | @vindex diff | |
174 | @vindex mm-uu-diff-groups-regexp | |
175 | Patches. This is intended for groups where diffs of committed files | |
176 | are automatically sent to. It only works in groups matching | |
177 | @code{mm-uu-diff-groups-regexp}. | |
178 | ||
179 | @end table | |
180 | ||
181 | @node Handles | |
182 | @section Handles | |
183 | ||
184 | A @acronym{MIME} handle is a list that fully describes a @acronym{MIME} | |
185 | component. | |
186 | ||
187 | The following macros can be used to access elements in a handle: | |
188 | ||
189 | @table @code | |
190 | @item mm-handle-buffer | |
191 | @findex mm-handle-buffer | |
192 | Return the buffer that holds the contents of the undecoded @acronym{MIME} | |
193 | part. | |
194 | ||
195 | @item mm-handle-type | |
196 | @findex mm-handle-type | |
197 | Return the parsed @code{Content-Type} of the part. | |
198 | ||
199 | @item mm-handle-encoding | |
200 | @findex mm-handle-encoding | |
201 | Return the @code{Content-Transfer-Encoding} of the part. | |
202 | ||
203 | @item mm-handle-undisplayer | |
204 | @findex mm-handle-undisplayer | |
205 | Return the object that can be used to remove the displayed part (if it | |
206 | has been displayed). | |
207 | ||
208 | @item mm-handle-set-undisplayer | |
209 | @findex mm-handle-set-undisplayer | |
210 | Set the undisplayer object. | |
211 | ||
212 | @item mm-handle-disposition | |
213 | @findex mm-handle-disposition | |
214 | Return the parsed @code{Content-Disposition} of the part. | |
215 | ||
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216 | @item mm-get-content-id |
217 | Returns the handle(s) referred to by @code{Content-ID}. | |
218 | ||
219 | @end table | |
220 | ||
221 | ||
222 | @node Display | |
223 | @section Display | |
224 | ||
225 | Functions for displaying, removing and saving. | |
226 | ||
227 | @table @code | |
228 | @item mm-display-part | |
229 | @findex mm-display-part | |
230 | Display the part. | |
231 | ||
232 | @item mm-remove-part | |
233 | @findex mm-remove-part | |
234 | Remove the part (if it has been displayed). | |
235 | ||
236 | @item mm-inlinable-p | |
237 | @findex mm-inlinable-p | |
238 | Say whether a @acronym{MIME} type can be displayed inline. | |
239 | ||
240 | @item mm-automatic-display-p | |
241 | @findex mm-automatic-display-p | |
242 | Say whether a @acronym{MIME} type should be displayed automatically. | |
243 | ||
244 | @item mm-destroy-part | |
245 | @findex mm-destroy-part | |
246 | Free all resources occupied by a part. | |
247 | ||
248 | @item mm-save-part | |
249 | @findex mm-save-part | |
250 | Offer to save the part in a file. | |
251 | ||
252 | @item mm-pipe-part | |
253 | @findex mm-pipe-part | |
254 | Offer to pipe the part to some process. | |
255 | ||
256 | @item mm-interactively-view-part | |
257 | @findex mm-interactively-view-part | |
258 | Prompt for a mailcap method to use to view the part. | |
259 | ||
260 | @end table | |
261 | ||
262 | ||
263 | @node Display Customization | |
264 | @section Display Customization | |
265 | ||
266 | @table @code | |
267 | ||
268 | @item mm-inline-media-tests | |
269 | @vindex mm-inline-media-tests | |
270 | This is an alist where the key is a @acronym{MIME} type, the second element | |
271 | is a function to display the part @dfn{inline} (i.e., inside Emacs), and | |
272 | the third element is a form to be @code{eval}ed to say whether the part | |
273 | can be displayed inline. | |
274 | ||
275 | This variable specifies whether a part @emph{can} be displayed inline, | |
276 | and, if so, how to do it. It does not say whether parts are | |
277 | @emph{actually} displayed inline. | |
278 | ||
279 | @item mm-inlined-types | |
280 | @vindex mm-inlined-types | |
281 | This, on the other hand, says what types are to be displayed inline, if | |
282 | they satisfy the conditions set by the variable above. It's a list of | |
283 | @acronym{MIME} media types. | |
284 | ||
285 | @item mm-automatic-display | |
286 | @vindex mm-automatic-display | |
287 | This is a list of types that are to be displayed ``automatically'', but | |
288 | only if the above variable allows it. That is, only inlinable parts can | |
289 | be displayed automatically. | |
290 | ||
291 | @item mm-automatic-external-display | |
292 | @vindex mm-automatic-external-display | |
293 | This is a list of types that will be displayed automatically in an | |
294 | external viewer. | |
295 | ||
296 | @item mm-keep-viewer-alive-types | |
297 | @vindex mm-keep-viewer-alive-types | |
298 | This is a list of media types for which the external viewer will not | |
299 | be killed when selecting a different article. | |
300 | ||
301 | @item mm-attachment-override-types | |
302 | @vindex mm-attachment-override-types | |
303 | Some @acronym{MIME} agents create parts that have a content-disposition of | |
304 | @samp{attachment}. This variable allows overriding that disposition and | |
305 | displaying the part inline. (Note that the disposition is only | |
306 | overridden if we are able to, and want to, display the part inline.) | |
307 | ||
308 | @item mm-discouraged-alternatives | |
309 | @vindex mm-discouraged-alternatives | |
310 | List of @acronym{MIME} types that are discouraged when viewing | |
311 | @samp{multipart/alternative}. Viewing agents are supposed to view the | |
312 | last possible part of a message, as that is supposed to be the richest. | |
313 | However, users may prefer other types instead, and this list says what | |
314 | types are most unwanted. If, for instance, @samp{text/html} parts are | |
315 | very unwanted, and @samp{text/richtext} parts are somewhat unwanted, | |
316 | you could say something like: | |
317 | ||
318 | @lisp | |
319 | (setq mm-discouraged-alternatives | |
320 | '("text/html" "text/richtext") | |
321 | mm-automatic-display | |
322 | (remove "text/html" mm-automatic-display)) | |
323 | @end lisp | |
324 | ||
61e66a15 | 325 | Adding @code{"image/.*"} might also be useful. Spammers use images as |
4dc5fe62 | 326 | the preferred part of @samp{multipart/alternative} messages, so you might |
7dafe00b | 327 | not notice there are other parts. See also |
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328 | @code{gnus-buttonized-mime-types}, @ref{MIME Commands, ,MIME Commands, |
329 | gnus, Gnus Manual}. After adding @code{"multipart/alternative"} to | |
330 | @code{gnus-buttonized-mime-types} you can choose manually which | |
331 | alternative you'd like to view. For example, you can set those | |
332 | variables like: | |
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333 | |
334 | @lisp | |
335 | (setq gnus-buttonized-mime-types | |
336 | '("multipart/alternative" "multipart/signed") | |
337 | mm-discouraged-alternatives | |
338 | '("text/html" "image/.*")) | |
339 | @end lisp | |
340 | ||
341 | In this case, Gnus will display radio buttons for such a kind of spam | |
342 | message as follows: | |
343 | ||
344 | @example | |
345 | 1. (*) multipart/alternative ( ) image/gif | |
346 | ||
347 | 2. (*) text/plain ( ) text/html | |
348 | @end example | |
3031d8b0 | 349 | |
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350 | @item mm-inline-large-images |
351 | @vindex mm-inline-large-images | |
f4dd4ae8 | 352 | When displaying inline images that are larger than the window, Emacs |
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353 | does not enable scrolling, which means that you cannot see the whole |
354 | image. To prevent this, the library tries to determine the image size | |
355 | before displaying it inline, and if it doesn't fit the window, the | |
356 | library will display it externally (e.g. with @samp{ImageMagick} or | |
357 | @samp{xv}). Setting this variable to @code{t} disables this check and | |
358 | makes the library display all inline images as inline, regardless of | |
359 | their size. | |
360 | ||
361 | @item mm-inline-override-types | |
362 | @vindex mm-inline-override-types | |
363 | @code{mm-inlined-types} may include regular expressions, for example to | |
364 | specify that all @samp{text/.*} parts be displayed inline. If a user | |
365 | prefers to have a type that matches such a regular expression be treated | |
366 | as an attachment, that can be accomplished by setting this variable to a | |
367 | list containing that type. For example assuming @code{mm-inlined-types} | |
368 | includes @samp{text/.*}, then including @samp{text/html} in this | |
369 | variable will cause @samp{text/html} parts to be treated as attachments. | |
370 | ||
371 | @item mm-text-html-renderer | |
372 | @vindex mm-text-html-renderer | |
373 | This selects the function used to render @acronym{HTML}. The predefined | |
374 | renderers are selected by the symbols @code{w3}, | |
375 | @code{w3m}@footnote{See @uref{http://emacs-w3m.namazu.org/} for more | |
376 | information about emacs-w3m}, @code{links}, @code{lynx}, | |
377 | @code{w3m-standalone} or @code{html2text}. If @code{nil} use an | |
378 | external viewer. You can also specify a function, which will be | |
379 | called with a @acronym{MIME} handle as the argument. | |
380 | ||
381 | @item mm-inline-text-html-with-images | |
382 | @vindex mm-inline-text-html-with-images | |
383 | Some @acronym{HTML} mails might have the trick of spammers using | |
384 | @samp{<img>} tags. It is likely to be intended to verify whether you | |
385 | have read the mail. You can prevent your personal informations from | |
386 | leaking by setting this option to @code{nil} (which is the default). | |
387 | It is currently ignored by Emacs/w3. For emacs-w3m, you may use the | |
388 | command @kbd{t} on the image anchor to show an image even if it is | |
389 | @code{nil}.@footnote{The command @kbd{T} will load all images. If you | |
390 | have set the option @code{w3m-key-binding} to @code{info}, use @kbd{i} | |
391 | or @kbd{I} instead.} | |
392 | ||
393 | @item mm-w3m-safe-url-regexp | |
394 | @vindex mm-w3m-safe-url-regexp | |
395 | A regular expression that matches safe URL names, i.e. URLs that are | |
396 | unlikely to leak personal information when rendering @acronym{HTML} | |
397 | email (the default value is @samp{\\`cid:}). If @code{nil} consider | |
398 | all URLs safe. | |
399 | ||
400 | @item mm-inline-text-html-with-w3m-keymap | |
401 | @vindex mm-inline-text-html-with-w3m-keymap | |
402 | You can use emacs-w3m command keys in the inlined text/html part by | |
403 | setting this option to non-@code{nil}. The default value is @code{t}. | |
404 | ||
405 | @item mm-external-terminal-program | |
406 | @vindex mm-external-terminal-program | |
407 | The program used to start an external terminal. | |
408 | ||
409 | @item mm-enable-external | |
410 | @vindex mm-enable-external | |
10ace8ea | 411 | Indicate whether external @acronym{MIME} handlers should be used. |
23f87bed | 412 | |
10ace8ea | 413 | If @code{t}, all defined external @acronym{MIME} handlers are used. If |
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414 | @code{nil}, files are saved to disk (@code{mailcap-save-binary-file}). |
415 | If it is the symbol @code{ask}, you are prompted before the external | |
416 | @acronym{MIME} handler is invoked. | |
417 | ||
418 | When you launch an attachment through mailcap (@pxref{mailcap}) an | |
10ace8ea | 419 | attempt is made to use a safe viewer with the safest options---this isn't |
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420 | the case if you save it to disk and launch it in a different way |
421 | (command line or double-clicking). Anyhow, if you want to be sure not | |
422 | to launch any external programs, set this variable to @code{nil} or | |
423 | @code{ask}. | |
424 | ||
425 | @end table | |
426 | ||
427 | @node Files and Directories | |
428 | @section Files and Directories | |
429 | ||
430 | @table @code | |
431 | ||
432 | @item mm-default-directory | |
433 | @vindex mm-default-directory | |
434 | The default directory for saving attachments. If @code{nil} use | |
435 | @code{default-directory}. | |
436 | ||
437 | @item mm-tmp-directory | |
438 | @vindex mm-tmp-directory | |
439 | Directory for storing temporary files. | |
440 | ||
441 | @item mm-file-name-rewrite-functions | |
442 | @vindex mm-file-name-rewrite-functions | |
443 | A list of functions used for rewriting file names of @acronym{MIME} | |
444 | parts. Each function is applied successively to the file name. | |
445 | Ready-made functions include | |
446 | ||
447 | @table @code | |
448 | @item mm-file-name-delete-control | |
449 | @findex mm-file-name-delete-control | |
450 | Delete all control characters. | |
451 | ||
452 | @item mm-file-name-delete-gotchas | |
453 | @findex mm-file-name-delete-gotchas | |
454 | Delete characters that could have unintended consequences when used | |
455 | with flawed shell scripts, i.e. @samp{|}, @samp{>} and @samp{<}; and | |
456 | @samp{-}, @samp{.} as the first character. | |
457 | ||
458 | @item mm-file-name-delete-whitespace | |
459 | @findex mm-file-name-delete-whitespace | |
460 | Remove all whitespace. | |
461 | ||
462 | @item mm-file-name-trim-whitespace | |
463 | @findex mm-file-name-trim-whitespace | |
464 | Remove leading and trailing whitespace. | |
465 | ||
466 | @item mm-file-name-collapse-whitespace | |
467 | @findex mm-file-name-collapse-whitespace | |
468 | Collapse multiple whitespace characters. | |
469 | ||
470 | @item mm-file-name-replace-whitespace | |
471 | @findex mm-file-name-replace-whitespace | |
472 | @vindex mm-file-name-replace-whitespace | |
473 | Replace whitespace with underscores. Set the variable | |
474 | @code{mm-file-name-replace-whitespace} to any other string if you do | |
475 | not like underscores. | |
476 | @end table | |
477 | ||
478 | The standard Emacs functions @code{capitalize}, @code{downcase}, | |
479 | @code{upcase} and @code{upcase-initials} might also prove useful. | |
480 | ||
481 | @item mm-path-name-rewrite-functions | |
482 | @vindex mm-path-name-rewrite-functions | |
483 | List of functions used for rewriting the full file names of @acronym{MIME} | |
484 | parts. This is used when viewing parts externally, and is meant for | |
485 | transforming the absolute name so that non-compliant programs can find | |
486 | the file where it's saved. | |
487 | ||
488 | @end table | |
489 | ||
490 | @node New Viewers | |
491 | @section New Viewers | |
492 | ||
493 | Here's an example viewer for displaying @code{text/enriched} inline: | |
494 | ||
495 | @lisp | |
496 | (defun mm-display-enriched-inline (handle) | |
497 | (let (text) | |
498 | (with-temp-buffer | |
499 | (mm-insert-part handle) | |
500 | (save-window-excursion | |
501 | (enriched-decode (point-min) (point-max)) | |
502 | (setq text (buffer-string)))) | |
503 | (mm-insert-inline handle text))) | |
504 | @end lisp | |
505 | ||
506 | We see that the function takes a @acronym{MIME} handle as its parameter. It | |
507 | then goes to a temporary buffer, inserts the text of the part, does some | |
508 | work on the text, stores the result, goes back to the buffer it was | |
509 | called from and inserts the result. | |
510 | ||
511 | The two important helper functions here are @code{mm-insert-part} and | |
512 | @code{mm-insert-inline}. The first function inserts the text of the | |
513 | handle in the current buffer. It handles charset and/or content | |
514 | transfer decoding. The second function just inserts whatever text you | |
515 | tell it to insert, but it also sets things up so that the text can be | |
516 | ``undisplayed'' in a convenient manner. | |
517 | ||
518 | ||
519 | @node Composing | |
520 | @chapter Composing | |
521 | @cindex Composing | |
522 | @cindex MIME Composing | |
523 | @cindex MML | |
524 | @cindex MIME Meta Language | |
525 | ||
526 | Creating a @acronym{MIME} message is boring and non-trivial. Therefore, | |
527 | a library called @code{mml} has been defined that parses a language | |
528 | called @acronym{MML} (@acronym{MIME} Meta Language) and generates | |
529 | @acronym{MIME} messages. | |
530 | ||
531 | @findex mml-generate-mime | |
532 | The main interface function is @code{mml-generate-mime}. It will | |
533 | examine the contents of the current (narrowed-to) buffer and return a | |
534 | string containing the @acronym{MIME} message. | |
535 | ||
536 | @menu | |
537 | * Simple MML Example:: An example @acronym{MML} document. | |
538 | * MML Definition:: All valid @acronym{MML} elements. | |
539 | * Advanced MML Example:: Another example @acronym{MML} document. | |
540 | * Encoding Customization:: Variables that affect encoding. | |
541 | * Charset Translation:: How charsets are mapped from @sc{mule} to @acronym{MIME}. | |
542 | * Conversion:: Going from @acronym{MIME} to @acronym{MML} and vice versa. | |
543 | * Flowed text:: Soft and hard newlines. | |
544 | @end menu | |
545 | ||
546 | ||
547 | @node Simple MML Example | |
548 | @section Simple MML Example | |
549 | ||
550 | Here's a simple @samp{multipart/alternative}: | |
551 | ||
552 | @example | |
553 | <#multipart type=alternative> | |
554 | This is a plain text part. | |
555 | <#part type=text/enriched> | |
556 | <center>This is a centered enriched part</center> | |
557 | <#/multipart> | |
558 | @end example | |
559 | ||
560 | After running this through @code{mml-generate-mime}, we get this: | |
561 | ||
562 | @example | |
563 | Content-Type: multipart/alternative; boundary="=-=-=" | |
564 | ||
565 | ||
566 | --=-=-= | |
567 | ||
568 | ||
569 | This is a plain text part. | |
570 | ||
571 | --=-=-= | |
572 | Content-Type: text/enriched | |
573 | ||
574 | ||
575 | <center>This is a centered enriched part</center> | |
576 | ||
577 | --=-=-=-- | |
578 | @end example | |
579 | ||
580 | ||
581 | @node MML Definition | |
582 | @section MML Definition | |
583 | ||
584 | The @acronym{MML} language is very simple. It looks a bit like an SGML | |
585 | application, but it's not. | |
586 | ||
587 | The main concept of @acronym{MML} is the @dfn{part}. Each part can be of a | |
588 | different type or use a different charset. The way to delineate a part | |
589 | is with a @samp{<#part ...>} tag. Multipart parts can be introduced | |
590 | with the @samp{<#multipart ...>} tag. Parts are ended by the | |
591 | @samp{<#/part>} or @samp{<#/multipart>} tags. Parts started with the | |
592 | @samp{<#part ...>} tags are also closed by the next open tag. | |
593 | ||
594 | There's also the @samp{<#external ...>} tag. These introduce | |
595 | @samp{external/message-body} parts. | |
596 | ||
597 | Each tag can contain zero or more parameters on the form | |
598 | @samp{parameter=value}. The values may be enclosed in quotation marks, | |
599 | but that's not necessary unless the value contains white space. So | |
600 | @samp{filename=/home/user/#hello$^yes} is perfectly valid. | |
601 | ||
602 | The following parameters have meaning in @acronym{MML}; parameters that have no | |
603 | meaning are ignored. The @acronym{MML} parameter names are the same as the | |
604 | @acronym{MIME} parameter names; the things in the parentheses say which | |
605 | header it will be used in. | |
606 | ||
607 | @table @samp | |
608 | @item type | |
609 | The @acronym{MIME} type of the part (@code{Content-Type}). | |
610 | ||
611 | @item filename | |
612 | Use the contents of the file in the body of the part | |
613 | (@code{Content-Disposition}). | |
614 | ||
615 | @item charset | |
616 | The contents of the body of the part are to be encoded in the character | |
617 | set specified (@code{Content-Type}). @xref{Charset Translation}. | |
618 | ||
619 | @item name | |
620 | Might be used to suggest a file name if the part is to be saved | |
621 | to a file (@code{Content-Type}). | |
622 | ||
623 | @item disposition | |
624 | Valid values are @samp{inline} and @samp{attachment} | |
625 | (@code{Content-Disposition}). | |
626 | ||
627 | @item encoding | |
628 | Valid values are @samp{7bit}, @samp{8bit}, @samp{quoted-printable} and | |
629 | @samp{base64} (@code{Content-Transfer-Encoding}). @xref{Charset | |
630 | Translation}. | |
631 | ||
632 | @item description | |
633 | A description of the part (@code{Content-Description}). | |
634 | ||
635 | @item creation-date | |
636 | RFC822 date when the part was created (@code{Content-Disposition}). | |
637 | ||
638 | @item modification-date | |
639 | RFC822 date when the part was modified (@code{Content-Disposition}). | |
640 | ||
641 | @item read-date | |
642 | RFC822 date when the part was read (@code{Content-Disposition}). | |
643 | ||
644 | @item recipients | |
645 | Who to encrypt/sign the part to. This field is used to override any | |
646 | auto-detection based on the To/CC headers. | |
647 | ||
648 | @item sender | |
649 | Identity used to sign the part. This field is used to override the | |
650 | default key used. | |
651 | ||
652 | @item size | |
653 | The size (in octets) of the part (@code{Content-Disposition}). | |
654 | ||
655 | @item sign | |
656 | What technology to sign this @acronym{MML} part with (@code{smime}, @code{pgp} | |
657 | or @code{pgpmime}) | |
658 | ||
659 | @item encrypt | |
660 | What technology to encrypt this @acronym{MML} part with (@code{smime}, | |
661 | @code{pgp} or @code{pgpmime}) | |
662 | ||
663 | @end table | |
664 | ||
665 | Parameters for @samp{text/plain}: | |
666 | ||
667 | @table @samp | |
668 | @item format | |
669 | Formatting parameter for the text, valid values include @samp{fixed} | |
670 | (the default) and @samp{flowed}. Normally you do not specify this | |
671 | manually, since it requires the textual body to be formatted in a | |
672 | special way described in RFC 2646. @xref{Flowed text}. | |
673 | @end table | |
674 | ||
675 | Parameters for @samp{application/octet-stream}: | |
676 | ||
677 | @table @samp | |
678 | @item type | |
679 | Type of the part; informal---meant for human readers | |
680 | (@code{Content-Type}). | |
681 | @end table | |
682 | ||
683 | Parameters for @samp{message/external-body}: | |
684 | ||
685 | @table @samp | |
686 | @item access-type | |
687 | A word indicating the supported access mechanism by which the file may | |
688 | be obtained. Values include @samp{ftp}, @samp{anon-ftp}, @samp{tftp}, | |
689 | @samp{localfile}, and @samp{mailserver}. (@code{Content-Type}.) | |
690 | ||
691 | @item expiration | |
692 | The RFC822 date after which the file may no longer be fetched. | |
693 | (@code{Content-Type}.) | |
694 | ||
695 | @item size | |
696 | The size (in octets) of the file. (@code{Content-Type}.) | |
697 | ||
698 | @item permission | |
699 | Valid values are @samp{read} and @samp{read-write} | |
700 | (@code{Content-Type}). | |
701 | ||
702 | @end table | |
703 | ||
704 | Parameters for @samp{sign=smime}: | |
705 | ||
706 | @table @samp | |
707 | ||
708 | @item keyfile | |
709 | File containing key and certificate for signer. | |
710 | ||
711 | @end table | |
712 | ||
713 | Parameters for @samp{encrypt=smime}: | |
714 | ||
715 | @table @samp | |
716 | ||
717 | @item certfile | |
718 | File containing certificate for recipient. | |
719 | ||
720 | @end table | |
721 | ||
722 | ||
723 | @node Advanced MML Example | |
724 | @section Advanced MML Example | |
725 | ||
726 | Here's a complex multipart message. It's a @samp{multipart/mixed} that | |
727 | contains many parts, one of which is a @samp{multipart/alternative}. | |
728 | ||
729 | @example | |
730 | <#multipart type=mixed> | |
731 | <#part type=image/jpeg filename=~/rms.jpg disposition=inline> | |
732 | <#multipart type=alternative> | |
733 | This is a plain text part. | |
734 | <#part type=text/enriched name=enriched.txt> | |
735 | <center>This is a centered enriched part</center> | |
736 | <#/multipart> | |
737 | This is a new plain text part. | |
738 | <#part disposition=attachment> | |
739 | This plain text part is an attachment. | |
740 | <#/multipart> | |
741 | @end example | |
742 | ||
743 | And this is the resulting @acronym{MIME} message: | |
744 | ||
745 | @example | |
746 | Content-Type: multipart/mixed; boundary="=-=-=" | |
747 | ||
748 | ||
749 | --=-=-= | |
750 | ||
751 | ||
752 | ||
753 | --=-=-= | |
754 | Content-Type: image/jpeg; | |
755 | filename="~/rms.jpg" | |
756 | Content-Disposition: inline; | |
757 | filename="~/rms.jpg" | |
758 | Content-Transfer-Encoding: base64 | |
759 | ||
760 | /9j/4AAQSkZJRgABAQAAAQABAAD/2wBDAAgGBgcGBQgHBwcJCQgKDBQNDAsLDBkSEw8UHRof | |
761 | Hh0aHBwgJC4nICIsIxwcKDcpLDAxNDQ0Hyc5PTgyPC4zNDL/wAALCAAwADABAREA/8QAHwAA | |
762 | AQUBAQEBAQEAAAAAAAAAAAECAwQFBgcICQoL/8QAtRAAAgEDAwIEAwUFBAQAAAF9AQIDAAQR | |
763 | BRIhMUEGE1FhByJxFDKBkaEII0KxwRVS0fAkM2JyggkKFhcYGRolJicoKSo0NTY3ODk6Q0RF | |
764 | RkdISUpTVFVWV1hZWmNkZWZnaGlqc3R1dnd4eXqDhIWGh4iJipKTlJWWl5iZmqKjpKWmp6ip | |
765 | qrKztLW2t7i5usLDxMXGx8jJytLT1NXW19jZ2uHi4+Tl5ufo6erx8vP09fb3+Pn6/9oACAEB | |
766 | AAA/AO/rifFHjldNuGsrDa0qcSSHkA+gHrXKw+LtWLrMb+RgTyhbr+HSug07xNqV9fQtZrNI | |
767 | AyiaE/NuBPOOOP0rvRNE880KOC8TbXXGCv1FPqjrF4LDR7u5L7SkTFT/ALWOP1xXgTuXfc7E | |
768 | sx6nua6rwp4IvvEM8chCxWxOdzn7wz6V9AaB4S07w9p5itow0rDLSY5Pt9K43xO66P4xs71m | |
769 | 2QXiGCbA4yOVJ9+1aYORkdK434lyNH4ahCnG66VT9Nj15JFbPdX0MS43M4VQf5/yr2vSpLnw | |
770 | 5ZW8dlCZ8KFXjOPX0/mK6rSPEGt3Angu44fNEReHYNvIH3TzXDeKNO8RX+kSX2ouZkicTIOc | |
771 | L+g7E810ulFjpVtv3bwgB3HJyK5L4quY/C9sVxk3ij/xx6850u7t1mtp/wDlpEw3An3Jr3Dw | |
772 | 34gsbWza4nBlhC5LDsaW6+IFgupQyCF3iHH7gA7c9R9ay7zx6t7aX9jHC4smhfBkGCvHGfrm | |
773 | tLQ7hbnRrV1GPkAP1x1/Hr+Ncr8Vzjwrbf8AX6v/AKA9eQRyYlQk8Yx9K6XTNbkgia2ciSIn | |
774 | 7p5Ga9Atte0LTLKO6it4i7dVRFJDcZ4PvXN+JvEMF9bILVGXJLSZ4zkjivRPDaeX4b08HOTC | |
775 | pOffmua+KkbS+GLVUGT9tT/0B68eeIpIFYjB70+OOVXyoOM9+M1eaWeCLzHPyHGO/NVWvJJm | |
776 | jQ8KGH1NfQWhXSXmh2c8eArRLwO3HSv/2Q== | |
777 | ||
778 | --=-=-= | |
779 | Content-Type: multipart/alternative; boundary="==-=-=" | |
780 | ||
781 | ||
782 | --==-=-= | |
783 | ||
784 | ||
785 | This is a plain text part. | |
786 | ||
787 | --==-=-= | |
788 | Content-Type: text/enriched; | |
789 | name="enriched.txt" | |
790 | ||
791 | ||
792 | <center>This is a centered enriched part</center> | |
793 | ||
794 | --==-=-=-- | |
795 | ||
796 | --=-=-= | |
797 | ||
798 | This is a new plain text part. | |
799 | ||
800 | --=-=-= | |
801 | Content-Disposition: attachment | |
802 | ||
803 | ||
804 | This plain text part is an attachment. | |
805 | ||
806 | --=-=-=-- | |
807 | @end example | |
808 | ||
809 | @node Encoding Customization | |
810 | @section Encoding Customization | |
811 | ||
812 | @table @code | |
813 | ||
814 | @item mm-body-charset-encoding-alist | |
815 | @vindex mm-body-charset-encoding-alist | |
816 | Mapping from @acronym{MIME} charset to encoding to use. This variable is | |
817 | usually used except, e.g., when other requirements force a specific | |
818 | encoding (digitally signed messages require 7bit encodings). The | |
3d80e1a2 | 819 | default is |
23f87bed MB |
820 | |
821 | @lisp | |
822 | ((iso-2022-jp . 7bit) | |
823 | (iso-2022-jp-2 . 7bit) | |
824 | (utf-16 . base64) | |
825 | (utf-16be . base64) | |
826 | (utf-16le . base64)) | |
827 | @end lisp | |
828 | ||
829 | As an example, if you do not want to have ISO-8859-1 characters | |
830 | quoted-printable encoded, you may add @code{(iso-8859-1 . 8bit)} to | |
831 | this variable. You can override this setting on a per-message basis | |
832 | by using the @code{encoding} @acronym{MML} tag (@pxref{MML Definition}). | |
833 | ||
834 | @item mm-coding-system-priorities | |
835 | @vindex mm-coding-system-priorities | |
836 | Prioritize coding systems to use for outgoing messages. The default | |
f3f01d5d MB |
837 | is @code{nil}, which means to use the defaults in Emacs, but is |
838 | @code{(iso-8859-1 iso-2022-jp iso-2022-jp-2 shift_jis utf-8)} when | |
839 | running Emacs in the Japanese language environment. It is a list of | |
0683d241 MB |
840 | coding system symbols (aliases of coding systems are also allowed, use |
841 | @kbd{M-x describe-coding-system} to make sure you are specifying correct | |
842 | coding system names). For example, if you have configured Emacs | |
23f87bed MB |
843 | to prefer UTF-8, but wish that outgoing messages should be sent in |
844 | ISO-8859-1 if possible, you can set this variable to | |
0683d241 | 845 | @code{(iso-8859-1)}. You can override this setting on a per-message |
23f87bed MB |
846 | basis by using the @code{charset} @acronym{MML} tag (@pxref{MML Definition}). |
847 | ||
848 | @item mm-content-transfer-encoding-defaults | |
849 | @vindex mm-content-transfer-encoding-defaults | |
850 | Mapping from @acronym{MIME} types to encoding to use. This variable is usually | |
851 | used except, e.g., when other requirements force a safer encoding | |
852 | (digitally signed messages require 7bit encoding). Besides the normal | |
853 | @acronym{MIME} encodings, @code{qp-or-base64} may be used to indicate that for | |
854 | each case the most efficient of quoted-printable and base64 should be | |
855 | used. | |
856 | ||
857 | @code{qp-or-base64} has another effect. It will fold long lines so that | |
858 | MIME parts may not be broken by MTA. So do @code{quoted-printable} and | |
859 | @code{base64}. | |
860 | ||
861 | Note that it affects body encoding only when a part is a raw forwarded | |
862 | message (which will be made by @code{gnus-summary-mail-forward} with the | |
863 | arg 2 for example) or is neither the @samp{text/*} type nor the | |
864 | @samp{message/*} type. Even though in those cases, you can override | |
865 | this setting on a per-message basis by using the @code{encoding} | |
866 | @acronym{MML} tag (@pxref{MML Definition}). | |
867 | ||
868 | @item mm-use-ultra-safe-encoding | |
869 | @vindex mm-use-ultra-safe-encoding | |
870 | When this is non-@code{nil}, it means that textual parts are encoded as | |
871 | quoted-printable if they contain lines longer than 76 characters or | |
872 | starting with "From " in the body. Non-7bit encodings (8bit, binary) | |
873 | are generally disallowed. This reduce the probability that a non-8bit | |
874 | clean MTA or MDA changes the message. This should never be set | |
875 | directly, but bound by other functions when necessary (e.g., when | |
876 | encoding messages that are to be digitally signed). | |
877 | ||
878 | @end table | |
879 | ||
880 | @node Charset Translation | |
881 | @section Charset Translation | |
882 | @cindex charsets | |
883 | ||
884 | During translation from @acronym{MML} to @acronym{MIME}, for each | |
885 | @acronym{MIME} part which has been composed inside Emacs, an appropriate | |
886 | charset has to be chosen. | |
887 | ||
888 | @vindex mail-parse-charset | |
889 | If you are running a non-@sc{mule} Emacs, this process is simple: If the | |
890 | part contains any non-@acronym{ASCII} (8-bit) characters, the @acronym{MIME} charset | |
891 | given by @code{mail-parse-charset} (a symbol) is used. (Never set this | |
892 | variable directly, though. If you want to change the default charset, | |
893 | please consult the documentation of the package which you use to process | |
894 | @acronym{MIME} messages. | |
895 | @xref{Various Message Variables, , Various Message Variables, message, | |
896 | Message Manual}, for example.) | |
897 | If there are only @acronym{ASCII} characters, the @acronym{MIME} charset US-ASCII is | |
898 | used, of course. | |
899 | ||
900 | @cindex MULE | |
901 | @cindex UTF-8 | |
902 | @cindex Unicode | |
903 | @vindex mm-mime-mule-charset-alist | |
904 | Things are slightly more complicated when running Emacs with @sc{mule} | |
905 | support. In this case, a list of the @sc{mule} charsets used in the | |
f3f01d5d MB |
906 | part is obtained, and the @sc{mule} charsets are translated to |
907 | @acronym{MIME} charsets by consulting the table provided by Emacs itself | |
908 | or the variable @code{mm-mime-mule-charset-alist} for XEmacs. | |
23f87bed MB |
909 | If this results in a single @acronym{MIME} charset, this is used to encode |
910 | the part. But if the resulting list of @acronym{MIME} charsets contains more | |
911 | than one element, two things can happen: If it is possible to encode the | |
912 | part via UTF-8, this charset is used. (For this, Emacs must support | |
913 | the @code{utf-8} coding system, and the part must consist entirely of | |
914 | characters which have Unicode counterparts.) If UTF-8 is not available | |
915 | for some reason, the part is split into several ones, so that each one | |
916 | can be encoded with a single @acronym{MIME} charset. The part can only be | |
917 | split at line boundaries, though---if more than one @acronym{MIME} charset is | |
918 | required to encode a single line, it is not possible to encode the part. | |
919 | ||
920 | When running Emacs with @sc{mule} support, the preferences for which | |
921 | coding system to use is inherited from Emacs itself. This means that | |
922 | if Emacs is set up to prefer UTF-8, it will be used when encoding | |
923 | messages. You can modify this by altering the | |
924 | @code{mm-coding-system-priorities} variable though (@pxref{Encoding | |
925 | Customization}). | |
926 | ||
927 | The charset to be used can be overridden by setting the @code{charset} | |
928 | @acronym{MML} tag (@pxref{MML Definition}) when composing the message. | |
929 | ||
930 | The encoding of characters (quoted-printable, 8bit etc) is orthogonal | |
931 | to the discussion here, and is controlled by the variables | |
932 | @code{mm-body-charset-encoding-alist} and | |
933 | @code{mm-content-transfer-encoding-defaults} (@pxref{Encoding | |
934 | Customization}). | |
935 | ||
936 | @node Conversion | |
937 | @section Conversion | |
938 | ||
939 | @findex mime-to-mml | |
940 | A (multipart) @acronym{MIME} message can be converted to @acronym{MML} | |
941 | with the @code{mime-to-mml} function. It works on the message in the | |
942 | current buffer, and substitutes @acronym{MML} markup for @acronym{MIME} | |
943 | boundaries. Non-textual parts do not have their contents in the buffer, | |
944 | but instead have the contents in separate buffers that are referred to | |
945 | from the @acronym{MML} tags. | |
946 | ||
947 | @findex mml-to-mime | |
948 | An @acronym{MML} message can be converted back to @acronym{MIME} by the | |
949 | @code{mml-to-mime} function. | |
950 | ||
951 | These functions are in certain senses ``lossy''---you will not get back | |
952 | an identical message if you run @code{mime-to-mml} and then | |
953 | @code{mml-to-mime}. Not only will trivial things like the order of the | |
954 | headers differ, but the contents of the headers may also be different. | |
955 | For instance, the original message may use base64 encoding on text, | |
956 | while @code{mml-to-mime} may decide to use quoted-printable encoding, and | |
957 | so on. | |
958 | ||
959 | In essence, however, these two functions should be the inverse of each | |
960 | other. The resulting contents of the message should remain equivalent, | |
961 | if not identical. | |
dd8839b0 | 962 | |
dd8839b0 | 963 | |
23f87bed MB |
964 | @node Flowed text |
965 | @section Flowed text | |
966 | @cindex format=flowed | |
dd8839b0 | 967 | |
23f87bed MB |
968 | The Emacs @acronym{MIME} library will respect the @code{use-hard-newlines} |
969 | variable (@pxref{Hard and Soft Newlines, ,Hard and Soft Newlines, | |
970 | emacs, Emacs Manual}) when encoding a message, and the | |
971 | ``format=flowed'' Content-Type parameter when decoding a message. | |
972 | ||
973 | On encoding text, regardless of @code{use-hard-newlines}, lines | |
974 | terminated by soft newline characters are filled together and wrapped | |
975 | after the column decided by @code{fill-flowed-encode-column}. | |
976 | Quotation marks (matching @samp{^>* ?}) are respected. The variable | |
977 | controls how the text will look in a client that does not support | |
978 | flowed text, the default is to wrap after 66 characters. If hard | |
979 | newline characters are not present in the buffer, no flow encoding | |
980 | occurs. | |
981 | ||
982 | On decoding flowed text, lines with soft newline characters are filled | |
983 | together and wrapped after the column decided by | |
984 | @code{fill-flowed-display-column}. The default is to wrap after | |
985 | @code{fill-column}. | |
dd8839b0 | 986 | |
ba0226dd MB |
987 | @table @code |
988 | @item mm-fill-flowed | |
989 | @vindex mm-fill-flowed | |
990 | If non-@code{nil} a format=flowed article will be displayed flowed. | |
991 | @end table | |
dd8839b0 DL |
992 | |
993 | ||
994 | @node Interface Functions | |
995 | @chapter Interface Functions | |
996 | @cindex interface functions | |
997 | @cindex mail-parse | |
998 | ||
999 | The @code{mail-parse} library is an abstraction over the actual | |
1000 | low-level libraries that are described in the next chapter. | |
1001 | ||
1002 | Standards change, and so programs have to change to fit in the new | |
1003 | mold. For instance, RFC2045 describes a syntax for the | |
23f87bed | 1004 | @code{Content-Type} header that only allows @acronym{ASCII} characters in the |
dd8839b0 | 1005 | parameter list. RFC2231 expands on RFC2045 syntax to provide a scheme |
23f87bed | 1006 | for continuation headers and non-@acronym{ASCII} characters. |
dd8839b0 DL |
1007 | |
1008 | The traditional way to deal with this is just to update the library | |
1009 | functions to parse the new syntax. However, this is sometimes the wrong | |
1010 | thing to do. In some instances it may be vital to be able to understand | |
1011 | both the old syntax as well as the new syntax, and if there is only one | |
1012 | library, one must choose between the old version of the library and the | |
1013 | new version of the library. | |
1014 | ||
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1015 | The Emacs @acronym{MIME} library takes a different tack. It defines a |
1016 | series of low-level libraries (@file{rfc2047.el}, @file{rfc2231.el} | |
1017 | and so on) that parses strictly according to the corresponding | |
1018 | standard. However, normal programs would not use the functions | |
1019 | provided by these libraries directly, but instead use the functions | |
1020 | provided by the @code{mail-parse} library. The functions in this | |
1021 | library are just aliases to the corresponding functions in the latest | |
1022 | low-level libraries. Using this scheme, programs get a consistent | |
1023 | interface they can use, and library developers are free to create | |
1024 | write code that handles new standards. | |
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1025 | |
1026 | The following functions are defined by this library: | |
1027 | ||
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1028 | @table @code |
1029 | @item mail-header-parse-content-type | |
1030 | @findex mail-header-parse-content-type | |
1031 | Parse a @code{Content-Type} header and return a list on the following | |
1032 | format: | |
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1033 | |
1034 | @lisp | |
1035 | ("type/subtype" | |
1036 | (attribute1 . value1) | |
1037 | (attribute2 . value2) | |
23f87bed | 1038 | ...) |
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1039 | @end lisp |
1040 | ||
1041 | Here's an example: | |
1042 | ||
1043 | @example | |
1044 | (mail-header-parse-content-type | |
1045 | "image/gif; name=\"b980912.gif\"") | |
1046 | @result{} ("image/gif" (name . "b980912.gif")) | |
1047 | @end example | |
1048 | ||
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1049 | @item mail-header-parse-content-disposition |
1050 | @findex mail-header-parse-content-disposition | |
1051 | Parse a @code{Content-Disposition} header and return a list on the same | |
1052 | format as the function above. | |
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23f87bed | 1054 | @item mail-content-type-get |
dd8839b0 | 1055 | @findex mail-content-type-get |
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1056 | Takes two parameters---a list on the format above, and an attribute. |
1057 | Returns the value of the attribute. | |
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1058 | |
1059 | @example | |
1060 | (mail-content-type-get | |
1061 | '("image/gif" (name . "b980912.gif")) 'name) | |
1062 | @result{} "b980912.gif" | |
1063 | @end example | |
1064 | ||
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1065 | @item mail-header-encode-parameter |
1066 | @findex mail-header-encode-parameter | |
1067 | Takes a parameter string and returns an encoded version of the string. | |
1068 | This is used for parameters in headers like @code{Content-Type} and | |
1069 | @code{Content-Disposition}. | |
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1071 | @item mail-header-remove-comments |
1072 | @findex mail-header-remove-comments | |
1073 | Return a comment-free version of a header. | |
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1074 | |
1075 | @example | |
1076 | (mail-header-remove-comments | |
1077 | "Gnus/5.070027 (Pterodactyl Gnus v0.27) (Finnish Landrace)") | |
1078 | @result{} "Gnus/5.070027 " | |
1079 | @end example | |
1080 | ||
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1081 | @item mail-header-remove-whitespace |
1082 | @findex mail-header-remove-whitespace | |
1083 | Remove linear white space from a header. Space inside quoted strings | |
1084 | and comments is preserved. | |
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1085 | |
1086 | @example | |
1087 | (mail-header-remove-whitespace | |
1088 | "image/gif; name=\"Name with spaces\"") | |
1089 | @result{} "image/gif;name=\"Name with spaces\"" | |
1090 | @end example | |
1091 | ||
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1092 | @item mail-header-get-comment |
1093 | @findex mail-header-get-comment | |
1094 | Return the last comment in a header. | |
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1095 | |
1096 | @example | |
1097 | (mail-header-get-comment | |
1098 | "Gnus/5.070027 (Pterodactyl Gnus v0.27) (Finnish Landrace)") | |
1099 | @result{} "Finnish Landrace" | |
1100 | @end example | |
1101 | ||
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1102 | @item mail-header-parse-address |
1103 | @findex mail-header-parse-address | |
1104 | Parse an address and return a list containing the mailbox and the | |
1105 | plaintext name. | |
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1106 | |
1107 | @example | |
1108 | (mail-header-parse-address | |
1109 | "Hrvoje Niksic <hniksic@@srce.hr>") | |
1110 | @result{} ("hniksic@@srce.hr" . "Hrvoje Niksic") | |
1111 | @end example | |
1112 | ||
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1113 | @item mail-header-parse-addresses |
1114 | @findex mail-header-parse-addresses | |
1115 | Parse a string with list of addresses and return a list of elements like | |
1116 | the one described above. | |
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1117 | |
1118 | @example | |
1119 | (mail-header-parse-addresses | |
1120 | "Hrvoje Niksic <hniksic@@srce.hr>, Steinar Bang <sb@@metis.no>") | |
1121 | @result{} (("hniksic@@srce.hr" . "Hrvoje Niksic") | |
1122 | ("sb@@metis.no" . "Steinar Bang")) | |
1123 | @end example | |
1124 | ||
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1125 | @item mail-header-parse-date |
1126 | @findex mail-header-parse-date | |
1127 | Parse a date string and return an Emacs time structure. | |
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1129 | @item mail-narrow-to-head |
1130 | @findex mail-narrow-to-head | |
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1131 | Narrow the buffer to the header section of the buffer. Point is placed |
1132 | at the beginning of the narrowed buffer. | |
1133 | ||
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1134 | @item mail-header-narrow-to-field |
1135 | @findex mail-header-narrow-to-field | |
1136 | Narrow the buffer to the header under point. Understands continuation | |
1137 | headers. | |
1138 | ||
1139 | @item mail-header-fold-field | |
1140 | @findex mail-header-fold-field | |
1141 | Fold the header under point. | |
1142 | ||
1143 | @item mail-header-unfold-field | |
1144 | @findex mail-header-unfold-field | |
1145 | Unfold the header under point. | |
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1147 | @item mail-header-field-value |
1148 | @findex mail-header-field-value | |
1149 | Return the value of the field under point. | |
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1151 | @item mail-encode-encoded-word-region |
1152 | @findex mail-encode-encoded-word-region | |
1153 | Encode the non-@acronym{ASCII} words in the region. For instance, | |
1154 |