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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 | ||
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12 | Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005 |
13 | 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 | ||
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325 | Adding @code{"image/.*"} might also be useful. Spammers use it as the |
326 | prefered part of @samp{multipart/alternative} messages. See also | |
327 | @code{gnus-buttonized-mime-types} (@pxref{MIME Commands, ,MIME Commands, | |
328 | gnus, Gnus Manual}), to which adding @code{"multipart/alternative"} | |
329 | enables you to choose manually one of two types those mails include. | |
330 | ||
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331 | @item mm-inline-large-images |
332 | @vindex mm-inline-large-images | |
f4dd4ae8 | 333 | When displaying inline images that are larger than the window, Emacs |
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334 | does not enable scrolling, which means that you cannot see the whole |
335 | image. To prevent this, the library tries to determine the image size | |
336 | before displaying it inline, and if it doesn't fit the window, the | |
337 | library will display it externally (e.g. with @samp{ImageMagick} or | |
338 | @samp{xv}). Setting this variable to @code{t} disables this check and | |
339 | makes the library display all inline images as inline, regardless of | |
340 | their size. | |
341 | ||
342 | @item mm-inline-override-types | |
343 | @vindex mm-inline-override-types | |
344 | @code{mm-inlined-types} may include regular expressions, for example to | |
345 | specify that all @samp{text/.*} parts be displayed inline. If a user | |
346 | prefers to have a type that matches such a regular expression be treated | |
347 | as an attachment, that can be accomplished by setting this variable to a | |
348 | list containing that type. For example assuming @code{mm-inlined-types} | |
349 | includes @samp{text/.*}, then including @samp{text/html} in this | |
350 | variable will cause @samp{text/html} parts to be treated as attachments. | |
351 | ||
352 | @item mm-text-html-renderer | |
353 | @vindex mm-text-html-renderer | |
354 | This selects the function used to render @acronym{HTML}. The predefined | |
355 | renderers are selected by the symbols @code{w3}, | |
356 | @code{w3m}@footnote{See @uref{http://emacs-w3m.namazu.org/} for more | |
357 | information about emacs-w3m}, @code{links}, @code{lynx}, | |
358 | @code{w3m-standalone} or @code{html2text}. If @code{nil} use an | |
359 | external viewer. You can also specify a function, which will be | |
360 | called with a @acronym{MIME} handle as the argument. | |
361 | ||
362 | @item mm-inline-text-html-with-images | |
363 | @vindex mm-inline-text-html-with-images | |
364 | Some @acronym{HTML} mails might have the trick of spammers using | |
365 | @samp{<img>} tags. It is likely to be intended to verify whether you | |
366 | have read the mail. You can prevent your personal informations from | |
367 | leaking by setting this option to @code{nil} (which is the default). | |
368 | It is currently ignored by Emacs/w3. For emacs-w3m, you may use the | |
369 | command @kbd{t} on the image anchor to show an image even if it is | |
370 | @code{nil}.@footnote{The command @kbd{T} will load all images. If you | |
371 | have set the option @code{w3m-key-binding} to @code{info}, use @kbd{i} | |
372 | or @kbd{I} instead.} | |
373 | ||
374 | @item mm-w3m-safe-url-regexp | |
375 | @vindex mm-w3m-safe-url-regexp | |
376 | A regular expression that matches safe URL names, i.e. URLs that are | |
377 | unlikely to leak personal information when rendering @acronym{HTML} | |
378 | email (the default value is @samp{\\`cid:}). If @code{nil} consider | |
379 | all URLs safe. | |
380 | ||
381 | @item mm-inline-text-html-with-w3m-keymap | |
382 | @vindex mm-inline-text-html-with-w3m-keymap | |
383 | You can use emacs-w3m command keys in the inlined text/html part by | |
384 | setting this option to non-@code{nil}. The default value is @code{t}. | |
385 | ||
386 | @item mm-external-terminal-program | |
387 | @vindex mm-external-terminal-program | |
388 | The program used to start an external terminal. | |
389 | ||
390 | @item mm-enable-external | |
391 | @vindex mm-enable-external | |
10ace8ea | 392 | Indicate whether external @acronym{MIME} handlers should be used. |
23f87bed | 393 | |
10ace8ea | 394 | If @code{t}, all defined external @acronym{MIME} handlers are used. If |
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395 | @code{nil}, files are saved to disk (@code{mailcap-save-binary-file}). |
396 | If it is the symbol @code{ask}, you are prompted before the external | |
397 | @acronym{MIME} handler is invoked. | |
398 | ||
399 | When you launch an attachment through mailcap (@pxref{mailcap}) an | |
10ace8ea | 400 | attempt is made to use a safe viewer with the safest options---this isn't |
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401 | the case if you save it to disk and launch it in a different way |
402 | (command line or double-clicking). Anyhow, if you want to be sure not | |
403 | to launch any external programs, set this variable to @code{nil} or | |
404 | @code{ask}. | |
405 | ||
406 | @end table | |
407 | ||
408 | @node Files and Directories | |
409 | @section Files and Directories | |
410 | ||
411 | @table @code | |
412 | ||
413 | @item mm-default-directory | |
414 | @vindex mm-default-directory | |
415 | The default directory for saving attachments. If @code{nil} use | |
416 | @code{default-directory}. | |
417 | ||
418 | @item mm-tmp-directory | |
419 | @vindex mm-tmp-directory | |
420 | Directory for storing temporary files. | |
421 | ||
422 | @item mm-file-name-rewrite-functions | |
423 | @vindex mm-file-name-rewrite-functions | |
424 | A list of functions used for rewriting file names of @acronym{MIME} | |
425 | parts. Each function is applied successively to the file name. | |
426 | Ready-made functions include | |
427 | ||
428 | @table @code | |
429 | @item mm-file-name-delete-control | |
430 | @findex mm-file-name-delete-control | |
431 | Delete all control characters. | |
432 | ||
433 | @item mm-file-name-delete-gotchas | |
434 | @findex mm-file-name-delete-gotchas | |
435 | Delete characters that could have unintended consequences when used | |
436 | with flawed shell scripts, i.e. @samp{|}, @samp{>} and @samp{<}; and | |
437 | @samp{-}, @samp{.} as the first character. | |
438 | ||
439 | @item mm-file-name-delete-whitespace | |
440 | @findex mm-file-name-delete-whitespace | |
441 | Remove all whitespace. | |
442 | ||
443 | @item mm-file-name-trim-whitespace | |
444 | @findex mm-file-name-trim-whitespace | |
445 | Remove leading and trailing whitespace. | |
446 | ||
447 | @item mm-file-name-collapse-whitespace | |
448 | @findex mm-file-name-collapse-whitespace | |
449 | Collapse multiple whitespace characters. | |
450 | ||
451 | @item mm-file-name-replace-whitespace | |
452 | @findex mm-file-name-replace-whitespace | |
453 | @vindex mm-file-name-replace-whitespace | |
454 | Replace whitespace with underscores. Set the variable | |
455 | @code{mm-file-name-replace-whitespace} to any other string if you do | |
456 | not like underscores. | |
457 | @end table | |
458 | ||
459 | The standard Emacs functions @code{capitalize}, @code{downcase}, | |
460 | @code{upcase} and @code{upcase-initials} might also prove useful. | |
461 | ||
462 | @item mm-path-name-rewrite-functions | |
463 | @vindex mm-path-name-rewrite-functions | |
464 | List of functions used for rewriting the full file names of @acronym{MIME} | |
465 | parts. This is used when viewing parts externally, and is meant for | |
466 | transforming the absolute name so that non-compliant programs can find | |
467 | the file where it's saved. | |
468 | ||
469 | @end table | |
470 | ||
471 | @node New Viewers | |
472 | @section New Viewers | |
473 | ||
474 | Here's an example viewer for displaying @code{text/enriched} inline: | |
475 | ||
476 | @lisp | |
477 | (defun mm-display-enriched-inline (handle) | |
478 | (let (text) | |
479 | (with-temp-buffer | |
480 | (mm-insert-part handle) | |
481 | (save-window-excursion | |
482 | (enriched-decode (point-min) (point-max)) | |
483 | (setq text (buffer-string)))) | |
484 | (mm-insert-inline handle text))) | |
485 | @end lisp | |
486 | ||
487 | We see that the function takes a @acronym{MIME} handle as its parameter. It | |
488 | then goes to a temporary buffer, inserts the text of the part, does some | |
489 | work on the text, stores the result, goes back to the buffer it was | |
490 | called from and inserts the result. | |
491 | ||
492 | The two important helper functions here are @code{mm-insert-part} and | |
493 | @code{mm-insert-inline}. The first function inserts the text of the | |
494 | handle in the current buffer. It handles charset and/or content | |
495 | transfer decoding. The second function just inserts whatever text you | |
496 | tell it to insert, but it also sets things up so that the text can be | |
497 | ``undisplayed'' in a convenient manner. | |
498 | ||
499 | ||
500 | @node Composing | |
501 | @chapter Composing | |
502 | @cindex Composing | |
503 | @cindex MIME Composing | |
504 | @cindex MML | |
505 | @cindex MIME Meta Language | |
506 | ||
507 | Creating a @acronym{MIME} message is boring and non-trivial. Therefore, | |
508 | a library called @code{mml} has been defined that parses a language | |
509 | called @acronym{MML} (@acronym{MIME} Meta Language) and generates | |
510 | @acronym{MIME} messages. | |
511 | ||
512 | @findex mml-generate-mime | |
513 | The main interface function is @code{mml-generate-mime}. It will | |
514 | examine the contents of the current (narrowed-to) buffer and return a | |
515 | string containing the @acronym{MIME} message. | |
516 | ||
517 | @menu | |
518 | * Simple MML Example:: An example @acronym{MML} document. | |
519 | * MML Definition:: All valid @acronym{MML} elements. | |
520 | * Advanced MML Example:: Another example @acronym{MML} document. | |
521 | * Encoding Customization:: Variables that affect encoding. | |
522 | * Charset Translation:: How charsets are mapped from @sc{mule} to @acronym{MIME}. | |
523 | * Conversion:: Going from @acronym{MIME} to @acronym{MML} and vice versa. | |
524 | * Flowed text:: Soft and hard newlines. | |
525 | @end menu | |
526 | ||
527 | ||
528 | @node Simple MML Example | |
529 | @section Simple MML Example | |
530 | ||
531 | Here's a simple @samp{multipart/alternative}: | |
532 | ||
533 | @example | |
534 | <#multipart type=alternative> | |
535 | This is a plain text part. | |
536 | <#part type=text/enriched> | |
537 | <center>This is a centered enriched part</center> | |
538 | <#/multipart> | |
539 | @end example | |
540 | ||
541 | After running this through @code{mml-generate-mime}, we get this: | |
542 | ||
543 | @example | |
544 | Content-Type: multipart/alternative; boundary="=-=-=" | |
545 | ||
546 | ||
547 | --=-=-= | |
548 | ||
549 | ||
550 | This is a plain text part. | |
551 | ||
552 | --=-=-= | |
553 | Content-Type: text/enriched | |
554 | ||
555 | ||
556 | <center>This is a centered enriched part</center> | |
557 | ||
558 | --=-=-=-- | |
559 | @end example | |
560 | ||
561 | ||
562 | @node MML Definition | |
563 | @section MML Definition | |
564 | ||
565 | The @acronym{MML} language is very simple. It looks a bit like an SGML | |
566 | application, but it's not. | |
567 | ||
568 | The main concept of @acronym{MML} is the @dfn{part}. Each part can be of a | |
569 | different type or use a different charset. The way to delineate a part | |
570 | is with a @samp{<#part ...>} tag. Multipart parts can be introduced | |
571 | with the @samp{<#multipart ...>} tag. Parts are ended by the | |
572 | @samp{<#/part>} or @samp{<#/multipart>} tags. Parts started with the | |
573 | @samp{<#part ...>} tags are also closed by the next open tag. | |
574 | ||
575 | There's also the @samp{<#external ...>} tag. These introduce | |
576 | @samp{external/message-body} parts. | |
577 | ||
578 | Each tag can contain zero or more parameters on the form | |
579 | @samp{parameter=value}. The values may be enclosed in quotation marks, | |
580 | but that's not necessary unless the value contains white space. So | |
581 | @samp{filename=/home/user/#hello$^yes} is perfectly valid. | |
582 | ||
583 | The following parameters have meaning in @acronym{MML}; parameters that have no | |
584 | meaning are ignored. The @acronym{MML} parameter names are the same as the | |
585 | @acronym{MIME} parameter names; the things in the parentheses say which | |
586 | header it will be used in. | |
587 | ||
588 | @table @samp | |
589 | @item type | |
590 | The @acronym{MIME} type of the part (@code{Content-Type}). | |
591 | ||
592 | @item filename | |
593 | Use the contents of the file in the body of the part | |
594 | (@code{Content-Disposition}). | |
595 | ||
596 | @item charset | |
597 | The contents of the body of the part are to be encoded in the character | |
598 | set specified (@code{Content-Type}). @xref{Charset Translation}. | |
599 | ||
600 | @item name | |
601 | Might be used to suggest a file name if the part is to be saved | |
602 | to a file (@code{Content-Type}). | |
603 | ||
604 | @item disposition | |
605 | Valid values are @samp{inline} and @samp{attachment} | |
606 | (@code{Content-Disposition}). | |
607 | ||
608 | @item encoding | |
609 | Valid values are @samp{7bit}, @samp{8bit}, @samp{quoted-printable} and | |
610 | @samp{base64} (@code{Content-Transfer-Encoding}). @xref{Charset | |
611 | Translation}. | |
612 | ||
613 | @item description | |
614 | A description of the part (@code{Content-Description}). | |
615 | ||
616 | @item creation-date | |
617 | RFC822 date when the part was created (@code{Content-Disposition}). | |
618 | ||
619 | @item modification-date | |
620 | RFC822 date when the part was modified (@code{Content-Disposition}). | |
621 | ||
622 | @item read-date | |
623 | RFC822 date when the part was read (@code{Content-Disposition}). | |
624 | ||
625 | @item recipients | |
626 | Who to encrypt/sign the part to. This field is used to override any | |
627 | auto-detection based on the To/CC headers. | |
628 | ||
629 | @item sender | |
630 | Identity used to sign the part. This field is used to override the | |
631 | default key used. | |
632 | ||
633 | @item size | |
634 | The size (in octets) of the part (@code{Content-Disposition}). | |
635 | ||
636 | @item sign | |
637 | What technology to sign this @acronym{MML} part with (@code{smime}, @code{pgp} | |
638 | or @code{pgpmime}) | |
639 | ||
640 | @item encrypt | |
641 | What technology to encrypt this @acronym{MML} part with (@code{smime}, | |
642 | @code{pgp} or @code{pgpmime}) | |
643 | ||
644 | @end table | |
645 | ||
646 | Parameters for @samp{text/plain}: | |
647 | ||
648 | @table @samp | |
649 | @item format | |
650 | Formatting parameter for the text, valid values include @samp{fixed} | |
651 | (the default) and @samp{flowed}. Normally you do not specify this | |
652 | manually, since it requires the textual body to be formatted in a | |
653 | special way described in RFC 2646. @xref{Flowed text}. | |
654 | @end table | |
655 | ||
656 | Parameters for @samp{application/octet-stream}: | |
657 | ||
658 | @table @samp | |
659 | @item type | |
660 | Type of the part; informal---meant for human readers | |
661 | (@code{Content-Type}). | |
662 | @end table | |
663 | ||
664 | Parameters for @samp{message/external-body}: | |
665 | ||
666 | @table @samp | |
667 | @item access-type | |
668 | A word indicating the supported access mechanism by which the file may | |
669 | be obtained. Values include @samp{ftp}, @samp{anon-ftp}, @samp{tftp}, | |
670 | @samp{localfile}, and @samp{mailserver}. (@code{Content-Type}.) | |
671 | ||
672 | @item expiration | |
673 | The RFC822 date after which the file may no longer be fetched. | |
674 | (@code{Content-Type}.) | |
675 | ||
676 | @item size | |
677 | The size (in octets) of the file. (@code{Content-Type}.) | |
678 | ||
679 | @item permission | |
680 | Valid values are @samp{read} and @samp{read-write} | |
681 | (@code{Content-Type}). | |
682 | ||
683 | @end table | |
684 | ||
685 | Parameters for @samp{sign=smime}: | |
686 | ||
687 | @table @samp | |
688 | ||
689 | @item keyfile | |
690 | File containing key and certificate for signer. | |
691 | ||
692 | @end table | |
693 | ||
694 | Parameters for @samp{encrypt=smime}: | |
695 | ||
696 | @table @samp | |
697 | ||
698 | @item certfile | |
699 | File containing certificate for recipient. | |
700 | ||
701 | @end table | |
702 | ||
703 | ||
704 | @node Advanced MML Example | |
705 | @section Advanced MML Example | |
706 | ||
707 | Here's a complex multipart message. It's a @samp{multipart/mixed} that | |
708 | contains many parts, one of which is a @samp{multipart/alternative}. | |
709 | ||
710 | @example | |
711 | <#multipart type=mixed> | |
712 | <#part type=image/jpeg filename=~/rms.jpg disposition=inline> | |
713 | <#multipart type=alternative> | |
714 | This is a plain text part. | |
715 | <#part type=text/enriched name=enriched.txt> | |
716 | <center>This is a centered enriched part</center> | |
717 | <#/multipart> | |
718 | This is a new plain text part. | |
719 | <#part disposition=attachment> | |
720 | This plain text part is an attachment. | |
721 | <#/multipart> | |
722 | @end example | |
723 | ||
724 | And this is the resulting @acronym{MIME} message: | |
725 | ||
726 | @example | |
727 | Content-Type: multipart/mixed; boundary="=-=-=" | |
728 | ||
729 | ||
730 | --=-=-= | |
731 | ||
732 | ||
733 | ||
734 | --=-=-= | |
735 | Content-Type: image/jpeg; | |
736 | filename="~/rms.jpg" | |
737 | Content-Disposition: inline; | |
738 | filename="~/rms.jpg" | |
739 | Content-Transfer-Encoding: base64 | |
740 | ||
741 | /9j/4AAQSkZJRgABAQAAAQABAAD/2wBDAAgGBgcGBQgHBwcJCQgKDBQNDAsLDBkSEw8UHRof | |
742 | Hh0aHBwgJC4nICIsIxwcKDcpLDAxNDQ0Hyc5PTgyPC4zNDL/wAALCAAwADABAREA/8QAHwAA | |
743 | AQUBAQEBAQEAAAAAAAAAAAECAwQFBgcICQoL/8QAtRAAAgEDAwIEAwUFBAQAAAF9AQIDAAQR | |
744 | BRIhMUEGE1FhByJxFDKBkaEII0KxwRVS0fAkM2JyggkKFhcYGRolJicoKSo0NTY3ODk6Q0RF | |
745 | RkdISUpTVFVWV1hZWmNkZWZnaGlqc3R1dnd4eXqDhIWGh4iJipKTlJWWl5iZmqKjpKWmp6ip | |
746 | qrKztLW2t7i5usLDxMXGx8jJytLT1NXW19jZ2uHi4+Tl5ufo6erx8vP09fb3+Pn6/9oACAEB | |
747 | AAA/AO/rifFHjldNuGsrDa0qcSSHkA+gHrXKw+LtWLrMb+RgTyhbr+HSug07xNqV9fQtZrNI | |
748 | AyiaE/NuBPOOOP0rvRNE880KOC8TbXXGCv1FPqjrF4LDR7u5L7SkTFT/ALWOP1xXgTuXfc7E | |
749 | sx6nua6rwp4IvvEM8chCxWxOdzn7wz6V9AaB4S07w9p5itow0rDLSY5Pt9K43xO66P4xs71m | |
750 | 2QXiGCbA4yOVJ9+1aYORkdK434lyNH4ahCnG66VT9Nj15JFbPdX0MS43M4VQf5/yr2vSpLnw | |
751 | 5ZW8dlCZ8KFXjOPX0/mK6rSPEGt3Angu44fNEReHYNvIH3TzXDeKNO8RX+kSX2ouZkicTIOc | |
752 | L+g7E810ulFjpVtv3bwgB3HJyK5L4quY/C9sVxk3ij/xx6850u7t1mtp/wDlpEw3An3Jr3Dw | |
753 | 34gsbWza4nBlhC5LDsaW6+IFgupQyCF3iHH7gA7c9R9ay7zx6t7aX9jHC4smhfBkGCvHGfrm | |
754 | tLQ7hbnRrV1GPkAP1x1/Hr+Ncr8Vzjwrbf8AX6v/AKA9eQRyYlQk8Yx9K6XTNbkgia2ciSIn | |
755 | 7p5Ga9Atte0LTLKO6it4i7dVRFJDcZ4PvXN+JvEMF9bILVGXJLSZ4zkjivRPDaeX4b08HOTC | |
756 | pOffmua+KkbS+GLVUGT9tT/0B68eeIpIFYjB70+OOVXyoOM9+M1eaWeCLzHPyHGO/NVWvJJm | |
757 | jQ8KGH1NfQWhXSXmh2c8eArRLwO3HSv/2Q== | |
758 | ||
759 | --=-=-= | |
760 | Content-Type: multipart/alternative; boundary="==-=-=" | |
761 | ||
762 | ||
763 | --==-=-= | |
764 | ||
765 | ||
766 | This is a plain text part. | |
767 | ||
768 | --==-=-= | |
769 | Content-Type: text/enriched; | |
770 | name="enriched.txt" | |
771 | ||
772 | ||
773 | <center>This is a centered enriched part</center> | |
774 | ||
775 | --==-=-=-- | |
776 | ||
777 | --=-=-= | |
778 | ||
779 | This is a new plain text part. | |
780 | ||
781 | --=-=-= | |
782 | Content-Disposition: attachment | |
783 | ||
784 | ||
785 | This plain text part is an attachment. | |
786 | ||
787 | --=-=-=-- | |
788 | @end example | |
789 | ||
790 | @node Encoding Customization | |
791 | @section Encoding Customization | |
792 | ||
793 | @table @code | |
794 | ||
795 | @item mm-body-charset-encoding-alist | |
796 | @vindex mm-body-charset-encoding-alist | |
797 | Mapping from @acronym{MIME} charset to encoding to use. This variable is | |
798 | usually used except, e.g., when other requirements force a specific | |
799 | encoding (digitally signed messages require 7bit encodings). The | |
3d80e1a2 | 800 | default is |
23f87bed MB |
801 | |
802 | @lisp | |
803 | ((iso-2022-jp . 7bit) | |
804 | (iso-2022-jp-2 . 7bit) | |
805 | (utf-16 . base64) | |
806 | (utf-16be . base64) | |
807 | (utf-16le . base64)) | |
808 | @end lisp | |
809 | ||
810 | As an example, if you do not want to have ISO-8859-1 characters | |
811 | quoted-printable encoded, you may add @code{(iso-8859-1 . 8bit)} to | |
812 | this variable. You can override this setting on a per-message basis | |
813 | by using the @code{encoding} @acronym{MML} tag (@pxref{MML Definition}). | |
814 | ||
815 | @item mm-coding-system-priorities | |
816 | @vindex mm-coding-system-priorities | |
817 | Prioritize coding systems to use for outgoing messages. The default | |
f3f01d5d MB |
818 | is @code{nil}, which means to use the defaults in Emacs, but is |
819 | @code{(iso-8859-1 iso-2022-jp iso-2022-jp-2 shift_jis utf-8)} when | |
820 | running Emacs in the Japanese language environment. It is a list of | |
0683d241 MB |
821 | coding system symbols (aliases of coding systems are also allowed, use |
822 | @kbd{M-x describe-coding-system} to make sure you are specifying correct | |
823 | coding system names). For example, if you have configured Emacs | |
23f87bed MB |
824 | to prefer UTF-8, but wish that outgoing messages should be sent in |
825 | ISO-8859-1 if possible, you can set this variable to | |
0683d241 | 826 | @code{(iso-8859-1)}. You can override this setting on a per-message |
23f87bed MB |
827 | basis by using the @code{charset} @acronym{MML} tag (@pxref{MML Definition}). |
828 | ||
829 | @item mm-content-transfer-encoding-defaults | |
830 | @vindex mm-content-transfer-encoding-defaults | |
831 | Mapping from @acronym{MIME} types to encoding to use. This variable is usually | |
832 | used except, e.g., when other requirements force a safer encoding | |
833 | (digitally signed messages require 7bit encoding). Besides the normal | |
834 | @acronym{MIME} encodings, @code{qp-or-base64} may be used to indicate that for | |
835 | each case the most efficient of quoted-printable and base64 should be | |
836 | used. | |
837 | ||
838 | @code{qp-or-base64} has another effect. It will fold long lines so that | |
839 | MIME parts may not be broken by MTA. So do @code{quoted-printable} and | |
840 | @code{base64}. | |
841 | ||
842 | Note that it affects body encoding only when a part is a raw forwarded | |
843 | message (which will be made by @code{gnus-summary-mail-forward} with the | |
844 | arg 2 for example) or is neither the @samp{text/*} type nor the | |
845 | @samp{message/*} type. Even though in those cases, you can override | |
846 | this setting on a per-message basis by using the @code{encoding} | |
847 | @acronym{MML} tag (@pxref{MML Definition}). | |
848 | ||
849 | @item mm-use-ultra-safe-encoding | |
850 | @vindex mm-use-ultra-safe-encoding | |
851 | When this is non-@code{nil}, it means that textual parts are encoded as | |
852 | quoted-printable if they contain lines longer than 76 characters or | |
853 | starting with "From " in the body. Non-7bit encodings (8bit, binary) | |
854 | are generally disallowed. This reduce the probability that a non-8bit | |
855 | clean MTA or MDA changes the message. This should never be set | |
856 | directly, but bound by other functions when necessary (e.g., when | |
857 | encoding messages that are to be digitally signed). | |
858 | ||
859 | @end table | |
860 | ||
861 | @node Charset Translation | |
862 | @section Charset Translation | |
863 | @cindex charsets | |
864 | ||
865 | During translation from @acronym{MML} to @acronym{MIME}, for each | |
866 | @acronym{MIME} part which has been composed inside Emacs, an appropriate | |
867 | charset has to be chosen. | |
868 | ||
869 | @vindex mail-parse-charset | |
870 | If you are running a non-@sc{mule} Emacs, this process is simple: If the | |
871 | part contains any non-@acronym{ASCII} (8-bit) characters, the @acronym{MIME} charset | |
872 | given by @code{mail-parse-charset} (a symbol) is used. (Never set this | |
873 | variable directly, though. If you want to change the default charset, | |
874 | please consult the documentation of the package which you use to process | |
875 | @acronym{MIME} messages. | |
876 | @xref{Various Message Variables, , Various Message Variables, message, | |
877 | Message Manual}, for example.) | |
878 | If there are only @acronym{ASCII} characters, the @acronym{MIME} charset US-ASCII is | |
879 | used, of course. | |
880 | ||
881 | @cindex MULE | |
882 | @cindex UTF-8 | |
883 | @cindex Unicode | |
884 | @vindex mm-mime-mule-charset-alist | |
885 | Things are slightly more complicated when running Emacs with @sc{mule} | |
886 | support. In this case, a list of the @sc{mule} charsets used in the | |
f3f01d5d MB |
887 | part is obtained, and the @sc{mule} charsets are translated to |
888 | @acronym{MIME} charsets by consulting the table provided by Emacs itself | |
889 | or the variable @code{mm-mime-mule-charset-alist} for XEmacs. | |
23f87bed MB |
890 | If this results in a single @acronym{MIME} charset, this is used to encode |
891 | the part. But if the resulting list of @acronym{MIME} charsets contains more | |
892 | than one element, two things can happen: If it is possible to encode the | |
893 | part via UTF-8, this charset is used. (For this, Emacs must support | |
894 | the @code{utf-8} coding system, and the part must consist entirely of | |
895 | characters which have Unicode counterparts.) If UTF-8 is not available | |
896 | for some reason, the part is split into several ones, so that each one | |
897 | can be encoded with a single @acronym{MIME} charset. The part can only be | |
898 | split at line boundaries, though---if more than one @acronym{MIME} charset is | |
899 | required to encode a single line, it is not possible to encode the part. | |
900 | ||
901 | When running Emacs with @sc{mule} support, the preferences for which | |
902 | coding system to use is inherited from Emacs itself. This means that | |
903 | if Emacs is set up to prefer UTF-8, it will be used when encoding | |
904 | messages. You can modify this by altering the | |
905 | @code{mm-coding-system-priorities} variable though (@pxref{Encoding | |
906 | Customization}). | |
907 | ||
908 | The charset to be used can be overridden by setting the @code{charset} | |
909 | @acronym{MML} tag (@pxref{MML Definition}) when composing the message. | |
910 | ||
911 | The encoding of characters (quoted-printable, 8bit etc) is orthogonal | |
912 | to the discussion here, and is controlled by the variables | |
913 | @code{mm-body-charset-encoding-alist} and | |
914 | @code{mm-content-transfer-encoding-defaults} (@pxref{Encoding | |
915 | Customization}). | |
916 | ||
917 | @node Conversion | |
918 | @section Conversion | |
919 | ||
920 | @findex mime-to-mml | |
921 | A (multipart) @acronym{MIME} message can be converted to @acronym{MML} | |
922 | with the @code{mime-to-mml} function. It works on the message in the | |
923 | current buffer, and substitutes @acronym{MML} markup for @acronym{MIME} | |
924 | boundaries. Non-textual parts do not have their contents in the buffer, | |
925 | but instead have the contents in separate buffers that are referred to | |
926 | from the @acronym{MML} tags. | |
927 | ||
928 | @findex mml-to-mime | |
929 | An @acronym{MML} message can be converted back to @acronym{MIME} by the | |
930 | @code{mml-to-mime} function. | |
931 | ||
932 | These functions are in certain senses ``lossy''---you will not get back | |
933 | an identical message if you run @code{mime-to-mml} and then | |
934 | @code{mml-to-mime}. Not only will trivial things like the order of the | |
935 | headers differ, but the contents of the headers may also be different. | |
936 | For instance, the original message may use base64 encoding on text, | |
937 | while @code{mml-to-mime} may decide to use quoted-printable encoding, and | |
938 | so on. | |
939 | ||
940 | In essence, however, these two functions should be the inverse of each | |
941 | other. The resulting contents of the message should remain equivalent, | |
942 | if not identical. | |
dd8839b0 | 943 | |
dd8839b0 | 944 | |
23f87bed MB |
945 | @node Flowed text |
946 | @section Flowed text | |
947 | @cindex format=flowed | |
dd8839b0 | 948 | |
23f87bed MB |
949 | The Emacs @acronym{MIME} library will respect the @code{use-hard-newlines} |
950 | variable (@pxref{Hard and Soft Newlines, ,Hard and Soft Newlines, | |
951 | emacs, Emacs Manual}) when encoding a message, and the | |
952 | ``format=flowed'' Content-Type parameter when decoding a message. | |
953 | ||
954 | On encoding text, regardless of @code{use-hard-newlines}, lines | |
955 | terminated by soft newline characters are filled together and wrapped | |
956 | after the column decided by @code{fill-flowed-encode-column}. | |
957 | Quotation marks (matching @samp{^>* ?}) are respected. The variable | |
958 | controls how the text will look in a client that does not support | |
959 | flowed text, the default is to wrap after 66 characters. If hard | |
960 | newline characters are not present in the buffer, no flow encoding | |
961 | occurs. | |
962 | ||
963 | On decoding flowed text, lines with soft newline characters are filled | |
964 | together and wrapped after the column decided by | |
965 | @code{fill-flowed-display-column}. The default is to wrap after | |
966 | @code{fill-column}. | |
dd8839b0 | 967 | |
dd8839b0 | 968 | |
dd8839b0 DL |
969 | |
970 | ||
971 | @node Interface Functions | |
972 | @chapter Interface Functions | |
973 | @cindex interface functions | |
974 | @cindex mail-parse | |
975 | ||
976 | The @code{mail-parse} library is an abstraction over the actual | |
977 | low-level libraries that are described in the next chapter. | |
978 | ||
979 | Standards change, and so programs have to change to fit in the new | |
980 | mold. For instance, RFC2045 describes a syntax for the | |
23f87bed | 981 | @code{Content-Type} header that only allows @acronym{ASCII} characters in the |
dd8839b0 | 982 | parameter list. RFC2231 expands on RFC2045 syntax to provide a scheme |
23f87bed | 983 | for continuation headers and non-@acronym{ASCII} characters. |
dd8839b0 DL |
984 | |
985 | The traditional way to deal with this is just to update the library | |
986 | functions to parse the new syntax. However, this is sometimes the wrong | |
987 | thing to do. In some instances it may be vital to be able to understand | |
988 | both the old syntax as well as the new syntax, and if there is only one | |
989 | library, one must choose between the old version of the library and the | |
990 | new version of the library. | |
991 | ||
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992 | The Emacs @acronym{MIME} library takes a different tack. It defines a |
993 | series of low-level libraries (@file{rfc2047.el}, @file{rfc2231.el} | |
994 | and so on) that parses strictly according to the corresponding | |
995 | standard. However, normal programs would not use the functions | |
996 | provided by these libraries directly, but instead use the functions | |
997 | provided by the @code{mail-parse} library. The functions in this | |
998 | library are just aliases to the corresponding functions in the latest | |
999 | low-level libraries. Using this scheme, programs get a consistent | |
1000 | interface they can use, and library developers are free to create | |
1001 | write code that handles new standards. | |
dd8839b0 DL |
1002 | |
1003 | The following functions are defined by this library: | |
1004 | ||
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1005 | @table @code |
1006 | @item mail-header-parse-content-type | |
1007 | @findex mail-header-parse-content-type | |
1008 | Parse a @code{Content-Type} header and return a list on the following | |
1009 | format: | |
dd8839b0 DL |
1010 | |
1011 | @lisp | |
1012 | ("type/subtype" | |
1013 | (attribute1 . value1) | |
1014 | (attribute2 . value2) | |
23f87bed | 1015 | ...) |
dd8839b0 DL |
1016 | @end lisp |
1017 | ||
1018 | Here's an example: | |
1019 | ||
1020 | @example | |
1021 | (mail-header-parse-content-type | |
1022 | "image/gif; name=\"b980912.gif\"") | |
1023 | @result{} ("image/gif" (name . "b980912.gif")) | |
1024 | @end example | |
1025 | ||
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1026 | @item mail-header-parse-content-disposition |
1027 | @findex mail-header-parse-content-disposition | |
1028 | Parse a @code{Content-Disposition} header and return a list on the same | |
1029 | format as the function above. | |
dd8839b0 | 1030 | |
23f87bed | 1031 | @item mail-content-type-get |
dd8839b0 | 1032 | @findex mail-content-type-get |
23f87bed MB |
1033 | Takes two parameters---a list on the format above, and an attribute. |
1034 | Returns the value of the attribute. | |
dd8839b0 DL |
1035 | |
1036 | @example | |
1037 | (mail-content-type-get | |
1038 | '("image/gif" (name . "b980912.gif")) 'name) | |
1039 | @result{} "b980912.gif" | |
1040 | @end example | |
1041 | ||
23f87bed MB |
1042 | @item mail-header-encode-parameter |
1043 | @findex mail-header-encode-parameter | |
1044 | Takes a parameter string and returns an encoded version of the string. | |
1045 | This is used for parameters in headers like @code{Content-Type} and | |
1046 | @code{Content-Disposition}. | |
dd8839b0 | 1047 | |
23f87bed MB |
1048 | @item mail-header-remove-comments |
1049 | @findex mail-header-remove-comments | |
1050 | Return a comment-free version of a header. | |
dd8839b0 DL |
1051 | |
1052 | @example | |
1053 | (mail-header-remove-comments | |
1054 | "Gnus/5.070027 (Pterodactyl Gnus v0.27) (Finnish Landrace)") | |
1055 | @result{} "Gnus/5.070027 " | |
1056 | @end example | |
1057 | ||
23f87bed MB |
1058 | @item mail-header-remove-whitespace |
1059 | @findex mail-header-remove-whitespace | |
1060 | Remove linear white space from a header. Space inside quoted strings | |
1061 | and comments is preserved. | |
dd8839b0 DL |
1062 | |
1063 | @example | |
1064 | (mail-header-remove-whitespace | |
1065 | "image/gif; name=\"Name with spaces\"") | |
1066 | @result{} "image/gif;name=\"Name with spaces\"" | |
1067 | @end example | |
1068 | ||
23f87bed MB |
1069 | @item mail-header-get-comment |
1070 | @findex mail-header-get-comment | |
1071 | Return the last comment in a header. | |
dd8839b0 DL |
1072 | |
1073 | @example | |
1074 | (mail-header-get-comment | |
1075 | "Gnus/5.070027 (Pterodactyl Gnus v0.27) (Finnish Landrace)") | |
1076 | @result{} "Finnish Landrace" | |
1077 | @end example | |
1078 | ||
23f87bed MB |
1079 | @item mail-header-parse-address |
1080 | @findex mail-header-parse-address | |
1081 | Parse an address and return a list containing the mailbox and the | |
1082 | plaintext name. | |
dd8839b0 DL |
1083 | |
1084 | @example | |
1085 | (mail-header-parse-address | |
1086 | "Hrvoje Niksic <hniksic@@srce.hr>") | |
1087 | @result{} ("hniksic@@srce.hr" . "Hrvoje Niksic") | |
1088 | @end example | |
1089 | ||
23f87bed MB |
1090 | @item mail-header-parse-addresses |
1091 | @findex mail-header-parse-addresses | |
1092 | Parse a string with list of addresses and return a list of elements like | |
1093 | the one described above. | |
dd8839b0 DL |
1094 | |
1095 | @example | |
1096 | (mail-header-parse-addresses | |
1097 | "Hrvoje Niksic <hniksic@@srce.hr>, Steinar Bang <sb@@metis.no>") | |
1098 | @result{} (("hniksic@@srce.hr" . "Hrvoje Niksic") | |
1099 | ("sb@@metis.no" . "Steinar Bang")) | |
1100 | @end example | |
1101 | ||
23f87bed MB |
1102 | @item mail-header-parse-date |
1103 | @findex mail-header-parse-date | |
1104 | Parse a date string and return an Emacs time structure. | |
dd8839b0 | 1105 | |
23f87bed MB |
1106 | @item mail-narrow-to-head |
1107 | @findex mail-narrow-to-head | |
dd8839b0 DL |
1108 | Narrow the buffer to the header section of the buffer. Point is placed |
1109 | at the beginning of the narrowed buffer. | |
1110 | ||
23f87bed MB |
1111 | @item mail-header-narrow-to-field |
1112 | @findex mail-header-narrow-to-field | |
1113 | Narrow the buffer to the header under point. Understands continuation | |
1114 | headers. | |
1115 | ||
1116 | @item mail-header-fold-field | |
1117 | @findex mail-header-fold-field | |
1118 | Fold the header under point. | |
1119 | ||
1120 | @item mail-header-unfold-field | |
1121 | @findex mail-header-unfold-field | |
1122 | Unfold the header under point. | |
dd8839b0 | 1123 | |
23f87bed MB |
1124 | @item mail-header-field-value |
1125 | @findex mail-header-field-value | |
1126 | Return the value of the field under point. | |
dd8839b0 | 1127 | |
23f87bed MB |
1128 | @item mail-encode-encoded-word-region |
1129 | @findex mail-encode-encoded-word-region | |
1130 | Encode the non-@acronym{ASCII} words in the region. For instance, | |
1131 |