In batch mode, the message is printed to the standard error stream,
followed by a newline.
+When @code{inhibit-message} is non-@code{nil}, no message will be displayed
+in the echo area, it will only be logged to @samp{*Messages*}.
+
If @var{format-string} is @code{nil} or the empty string,
@code{message} clears the echo area; if the echo area has been
expanded automatically, this brings it back to its normal size. If
depending on its size, use @code{display-message-or-buffer} (see below).
@end defun
+@defvar inhibit-message
+When this variable is non-@code{nil}, @code{message} and related functions
+will not use the Echo Area to display messages.
+@end defvar
+
@defmac with-temp-message message &rest body
This construct displays a message in the echo area temporarily, during
the execution of @var{body}. It displays @var{message}, executes
these affect the display of the text within the overlay.
@cindex scalability of overlays
+@cindex overlays, scalability
The visual effect of an overlay is the same as of the corresponding
text property (@pxref{Text Properties}). However, due to a different
implementation, overlays generally don't scale well (many operations
markers. If @var{buffer} is omitted, the overlay is created in the
current buffer.
+@cindex empty overlay
+@cindex overlay, empty
+An overlay whose @var{start} and @var{end} specify the same buffer
+position is known as @dfn{empty}. A non-empty overlay can become
+empty if the text between its @var{start} and @var{end} is deleted.
+When that happens, the overlay is by default not deleted, but you can
+cause it to be deleted by giving it the @samp{evaporate} property
+(@pxref{Overlay Properties, evaporate property}).
+
The arguments @var{front-advance} and @var{rear-advance} specify the
marker insertion type for the start of the overlay and for the end of
the overlay, respectively. @xref{Marker Insertion Types}. If they
@kindex evaporate @r{(overlay property)}
If this property is non-@code{nil}, the overlay is deleted automatically
if it becomes empty (i.e., if its length becomes zero). If you give
-an empty overlay a non-@code{nil} @code{evaporate} property, that deletes
-it immediately.
+an empty overlay (@pxref{Managing Overlays, empty overlay}) a
+non-@code{nil} @code{evaporate} property, that deletes it immediately.
+Note that, unless an overlay has this property, it will not be deleted
+when the text between its starting and ending positions is deleted
+from the buffer.
@item keymap
@cindex keymap of character (and overlays)
This function returns a list of the overlays that overlap the region
@var{beg} through @var{end}. ``Overlap'' means that at least one
character is contained within the overlay and also contained within the
-specified region; however, empty overlays are included in the result if
-they are located at @var{beg}, strictly between @var{beg} and @var{end},
-or at @var{end} when @var{end} denotes the position at the end of the
-buffer.
+specified region; however, empty overlays (@pxref{Managing Overlays,
+empty overlay}) are included in the result if they are located at
+@var{beg}, strictly between @var{beg} and @var{end}, or at @var{end}
+when @var{end} denotes the position at the end of the buffer.
@end defun
@defun next-overlay-change pos
functions instead of setting @code{face-remapping-alist} directly, to
avoid trampling on remappings applied elsewhere. These functions are
intended for buffer-local remappings, so they all make
-@code{face-remapping-alist} buffer-local as a side-effect. They manage
+@code{face-remapping-alist} buffer-local as a side-effect. They manage
@code{face-remapping-alist} entries of the form
@example
if you need to remove the remapping later.
@example
-;; Remap the `escape-glyph' face into a combination
-;; of the `highlight' and `italic' faces:
+;; Remap the 'escape-glyph' face into a combination
+;; of the 'highlight' and 'italic' faces:
(face-remap-add-relative 'escape-glyph 'highlight 'italic)
-;; Increase the size of the `default' face by 50%:
+;; Increase the size of the 'default' face by 50%:
(face-remap-add-relative 'default :height 1.5)
@end example
@end defun
@defun set-fontset-font name character font-spec &optional frame add
This function modifies the existing fontset @var{name} to use the font
-matching with @var{font-spec} for the character @var{character}.
+matching with @var{font-spec} for the specified @var{character}.
If @var{name} is @code{nil}, this function modifies the fontset of the
selected frame or that of @var{frame} if @var{frame} is not
If @var{name} is @code{t}, this function modifies the default
fontset, whose short name is @samp{fontset-default}.
-@var{character} may be a cons; @code{(@var{from} . @var{to})}, where
-@var{from} and @var{to} are character codepoints. In that case, use
-@var{font-spec} for all characters in the range @var{from} and @var{to}
-(inclusive).
+In addition to specifying a single codepoint, @var{character} may be a
+cons @code{(@var{from} . @var{to})}, where @var{from} and @var{to} are
+character codepoints. In that case, use @var{font-spec} for all the
+characters in the range @var{from} and @var{to} (inclusive).
@var{character} may be a charset. In that case, use
@var{font-spec} for all character in the charsets.
@var{character} may be a script name. In that case, use
@var{font-spec} for all character in the charsets.
+@var{font-spec} may be a font-spec object created by the function
+@code{font-spec} (@pxref{Low-Level Font}).
+
@var{font-spec} may be a cons; @code{(@var{family} . @var{registry})},
where @var{family} is a family name of a font (possibly including a
foundry name at the head), @var{registry} is a registry name of a font
@var{font-spec} may be a font name string.
+@var{font-spec} may be @code{nil}, which explicitly specifies that
+there's no font for the specified @var{character}. This is useful,
+for example, to avoid expensive system-wide search for fonts for
+characters that have no glyphs, like those from the Unicode Private
+Use Area (PUA).
+
The optional argument @var{add}, if non-@code{nil}, specifies how to
add @var{font-spec} to the font specifications previously set. If it
is @code{prepend}, @var{font-spec} is prepended. If it is
@item :script
The script that the font must support (a symbol).
+@item :lang
+The language that the font should support. The value should be a
+symbol whose name is a two-letter ISO-639 language name. On X, the
+value is matched against the ``Additional Style'' field of the XLFD
+name of a font, if it is non-empty. On MS-Windows, fonts matching the
+spec are required to support codepages needed for the language.
+Currently, only a small set of CJK languages is supported with this
+property: @samp{ja}, @samp{ko}, and @samp{zh}.
+
@item :otf
@cindex OpenType font
The font must be an OpenType font that supports these OpenType
faces used for the text.
@end table
-@c We put all the `@code{(when ...)}' on one line to encourage
+@c We put all the '@code{(when ...)}' on one line to encourage
@c makeinfo's end-of-sentence heuristics to DTRT. Previously, the dot
@c was at eol; the info file ended up w/ two spaces rendered after it.
You can make any display specification conditional. To do that,
specific tasks.
@defun define-button-type name &rest properties
-Define a `button type' called @var{name} (a symbol).
+Define a ``button type'' called @var{name} (a symbol).
The remaining arguments
form a sequence of @var{property value} pairs, specifying default
property values for buttons with this type (a button's type may be set
These are commands and functions for locating and operating on
buttons in an Emacs buffer.
-@code{push-button} is the command that a user uses to actually `push'
+@code{push-button} is the command that a user uses to actually ``push''
a button, and is bound by default in the button itself to @key{RET}
and to @key{mouse-2} using a local keymap in the button's overlay or
text properties. Commands that are useful outside the buttons itself,
@defvar standard-display-table
The value of this variable is the standard display table, which is
used when Emacs is displaying a buffer in a window with neither a
-window display table nor a buffer display table defined. Its default
-is @code{nil}.
+window display table nor a buffer display table defined, or when Emacs
+is outputting text to the standard output or error streams. Its
+default is @code{nil}.
@end defvar
The @file{disp-table} library defines several functions for changing
hexadecimal notation.
@item an @acronym{ASCII} string
-Display a box containing that string.
+Display a box containing that string. The string should contain at
+most 6 @acronym{ASCII} characters.
@item a cons cell @code{(@var{graphical} . @var{text})}
Display with @var{graphical} on graphical displays, and with
@noindent
The @code{thin-space}, @code{empty-box}, @code{hex-code}, and
@acronym{ASCII} string display methods are drawn with the
-@code{glyphless-char} face.
+@code{glyphless-char} face. On text terminals, a box is emulated by
+square brackets, @samp{[]}.
The char-table has one extra slot, which determines how to display any
character that cannot be displayed with any available font, or cannot
@samp{\230}).
@item format-control
-Characters of Unicode General Category `Cf', such as @samp{U+200E}
+Characters of Unicode General Category ``Cf'', such as @samp{U+200E}
(Left-to-Right Mark), but excluding characters that have graphic
images, such as @samp{U+00AD} (Soft Hyphen).
by the terminal's coding system.
@end table
-@c FIXME: this can also be `acronym', but that's not currently
+@c FIXME: this can also be 'acronym', but that's not currently
@c completely implemented; it applies only to the format-control
-@c group, and only works if the acronym is in `char-acronym-table'.
+@c group, and only works if the acronym is in 'char-acronym-table'.
The @var{method} symbol should be one of @code{zero-width},
@code{thin-space}, @code{empty-box}, or @code{hex-code}. These have
the same meanings as in @code{glyphless-char-display}, above.