* Handles:: Handle manipulations.
* Display:: Displaying handles.
* Customization:: Variables that affect display.
+* New Viewers:: How to write your own viewers.
@end menu
and, if so, how to do it. It does not say whether parts are
@emph{actually} displayed inline.
-@item mm-inlines-types
+@item mm-inlined-types
This, on the other hand, says what types are to be displayed inline, if
they satisfy the conditions set by the variable above. It's a list of
@sc{mime} media types.
@item mm-automatic-display
This is a list of types that are to be displayed ``automatically'', but
-only if the above variable allows it. That is, only inlinable parts are
-usually displayed automatically, but in the end, this is up to the
-display agent that's using the @sc{mime} library.
+only if the above variable allows it. That is, only inlinable parts can
+be displayed automatically.
@item mm-attachment-override-types
Some @sc{mime} agents create parts that have a content-disposition of
@samp{attachment}. This variable allows overriding that disposition and
-displaying the part inline.
+displaying the part inline. (Note that the disposition is only
+overridden if we are able to, and want to, display the part inline.)
@item mm-discouraged-alternatives
List of @sc{mime} types that are discouraged when viewing
("text/html" "text/richtext")
@end lisp
-@item mm-all-images-fit
-If non-@code{nil}, all images will be deemed to fit into the buffer,
-even when they don't.
+@item mm-inline-large-images-p
+When displaying inline images that are larger than the window, XEmacs
+does not enable scrolling, which means that you cannot see the whole
+image. To prevent this, the library tries to determine the image size
+before displaying it inline, and if it doesn't fit the window, the
+library will display it externally (e.g. with @samp{ImageMagick} or
+@samp{xv}). Setting this variable to @code{t} disables this check and
+makes the library display all inline images as inline, regardless of
+their size.
+
+@item mm-inline-override-p
+@code{mm-inlined-types} may include regular expressions, for example to
+specify that all @samp{text/.*} parts be displayed inline. If a user
+prefers to have a type that matches such a regular expression be treated
+as an attachment, that can be accomplished by setting this variable to a
+list containing that type. For example assuming @code{mm-inlined-types}
+includes @samp{text/.*}, then including @samp{text/html} in this
+variable will cause @samp{text/html} parts to be treated as attachments.
@end table
+@node New Viewers
+@section New Viewers
+
+Here's an example viewer for displaying @code{text/enriched} inline:
+
+@lisp
+(defun mm-display-enriched-inline (handle)
+ (let (text)
+ (with-temp-buffer
+ (mm-insert-part handle)
+ (save-window-excursion
+ (enriched-decode (point-min) (point-max))
+ (setq text (buffer-string))))
+ (mm-insert-inline handle text)))
+@end lisp
+
+We see that the function takes a @sc{mime} handle as its parameter. It
+then goes to a temporary buffer, inserts the text of the part, does some
+work on the text, stores the result, goes back to the buffer it was
+called from and inserts the result.
+
+The two important helper functions here are @code{mm-insert-part} and
+@code{mm-insert-inline}. The first function inserts the text of the
+handle in the current buffer. It handles charset and/or content
+transfer decoding. The second function just inserts whatever text you
+tell it to insert, but it also sets things up so that the text can be
+``undisplayed' in a convenient manner.
+
@node Composing
@chapter Composing
* Simple MML Example:: An example MML document.
* MML Definition:: All valid MML elements.
* Advanced MML Example:: Another example MML document.
+* Charset Translation:: How charsets are mapped from @sc{mule} to MIME.
* Conversion:: Going from @sc{mime} to MML and vice versa.
@end menu
--=-=-=--
@end example
+@node Charset Translation
+@section Charset Translation
+@cindex charsets
+
+During translation from MML to @sc{mime}, for each @sc{mime} part which
+has been composed inside Emacs, an appropriate charset has to be chosen.
+
+@vindex mail-parse-charset
+If you are running a non-@sc{mule} Emacs, this process is simple: If the
+part contains any non-ASCII (8-bit) characters, the @sc{mime} charset
+given by @code{mail-parse-charset} (a symbol) is used. (Never set this
+variable directly, though. If you want to change the default charset,
+please consult the documentation of the package which you use to process
+@sc{mime} messages.
+@xref{Various Message Variables, , Various Message Variables, message,
+ Message Manual}, for example.)
+If there are only ASCII characters, the @sc{mime} charset US-ASCII is
+used, of course.
+
+@cindex MULE
+@cindex UTF-8
+@cindex Unicode
+@vindex mm-mime-mule-charset-alist
+Things are slightly more complicated when running Emacs with @sc{mule}
+support. In this case, a list of the @sc{mule} charsets used in the
+part is obtained, and the @sc{mule} charsets are translated to @sc{mime}
+charsets by consulting the variable @code{mm-mime-mule-charset-alist}.
+If this results in a single @sc{mime} charset, this is used to encode
+the part. But if the resulting list of @sc{mime} charsets contains more
+than one element, two things can happen: If it is possible to encode the
+part via UTF-8, this charset is used. (For this, Emacs must support
+the @code{utf-8} coding system, and the part must consist entirely of
+characters which have Unicode counterparts.) If UTF-8 is not available
+for some reason, the part is split into several ones, so that each one
+can be encoded with a single @sc{mime} charset. The part can only be
+split at line boundaries, though---if more than one @sc{mime} charset is
+required to encode a single line, it is not possible to encode the part.
@node Conversion
@section Conversion
The Emacs @sc{mime} library implements handling of various elements
according to a (somewhat) large number of RFCs, drafts and standards
documents. This chapter lists the relevant ones. They can all be
-fetched from @samp{http://www.stud.ifi.uio.no/~larsi/notes/}.
+fetched from @samp{http://quimby.gnus.org/notes/}.
@table @dfn
@item RFC822
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