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diff --git a/doc/emacs/display.texi b/doc/emacs/display.texi new file mode 100644 index 00000000000..d4d2945d584 --- /dev/null +++ b/doc/emacs/display.texi @@ -0,0 +1,1259 @@ +@c This is part of the Emacs manual. +@c Copyright (C) 1985, 1986, 1987, 1993, 1994, 1995, 1997, 2000, 2001, +@c 2002, 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc. +@c See file emacs.texi for copying conditions. +@node Display, Search, Registers, Top +@chapter Controlling the Display + + Since only part of a large buffer fits in the window, Emacs tries to +show a part that is likely to be interesting. Display-control +commands allow you to specify which part of the text you want to see, +and how to display it. Many variables also affect the details of +redisplay. Unless otherwise stated, the variables described in this +chapter have their effect by customizing redisplay itself; therefore, +their values only make a difference at the time of redisplay. + +@menu +* Scrolling:: Commands to move text up and down in a window. +* Auto Scrolling:: Redisplay scrolls text automatically when needed. +* Horizontal Scrolling:: Moving text left and right in a window. +* Follow Mode:: Follow mode lets two windows scroll as one. +* Faces:: How to change the display style using faces. +* Standard Faces:: Emacs' predefined faces. +* Font Lock:: Minor mode for syntactic highlighting using faces. +* Highlight Interactively:: Tell Emacs what text to highlight. +* Fringes:: Enabling or disabling window fringes. +* Displaying Boundaries:: Displaying top and bottom of the buffer. +* Useless Whitespace:: Showing possibly-spurious trailing whitespace. +* Selective Display:: Hiding lines with lots of indentation. +* Optional Mode Line:: Optional mode line display features. +* Text Display:: How text characters are normally displayed. +* Cursor Display:: Features for displaying the cursor. +* Line Truncation:: Truncating lines to fit the screen width instead + of continuing them to multiple screen lines. +* Display Custom:: Information on variables for customizing display. +@end menu + +@node Scrolling +@section Scrolling + + If a buffer contains text that is too large to fit entirely within a +window that is displaying the buffer, Emacs shows a contiguous portion of +the text. The portion shown always contains point. + +@cindex scrolling + @dfn{Scrolling} means moving text up or down in the window so that +different parts of the text are visible. Scrolling ``forward'' or +``up'' means that text moves up, and new text appears at the bottom. +Scrolling ``backward'' or ``down'' moves text down, and new text +appears at the top. + + Scrolling happens automatically if you move point past the bottom or +top of the window. You can also scroll explicitly with the commands +in this section. + +@table @kbd +@item C-l +Clear screen and redisplay, scrolling the selected window to center +point vertically within it (@code{recenter}). +@item C-v +Scroll forward (a windowful or a specified number of lines) (@code{scroll-up}). +@item @key{NEXT} +@itemx @key{PAGEDOWN} +Likewise, scroll forward. +@item M-v +Scroll backward (@code{scroll-down}). +@item @key{PRIOR} +@itemx @key{PAGEUP} +Likewise, scroll backward. +@item @var{arg} C-l +Scroll so point is on line @var{arg} (@code{recenter}). +@item C-M-l +Scroll heuristically to bring useful information onto the screen +(@code{reposition-window}). +@end table + +@kindex C-l +@findex recenter + The most basic scrolling command is @kbd{C-l} (@code{recenter}) with +no argument. It scrolls the selected window so that point is halfway +down from the top of the window. On a text terminal, it also clears +the screen and redisplays all windows. That is useful in case the +screen is garbled (@pxref{Screen Garbled}). + +@kindex C-v +@kindex M-v +@kindex NEXT +@kindex PRIOR +@kindex PAGEDOWN +@kindex PAGEUP +@findex scroll-up +@findex scroll-down + To read the buffer a windowful at a time, use @kbd{C-v} +(@code{scroll-up}) with no argument. This scrolls forward by nearly +the whole window height. The effect is to take the two lines at the +bottom of the window and put them at the top, followed by nearly a +whole windowful of lines that were not previously visible. If point +was in the text that scrolled off the top, it ends up at the new top +of the window. + +@vindex next-screen-context-lines + @kbd{M-v} (@code{scroll-down}) with no argument scrolls backward in +a similar way, also with overlap. The number of lines of overlap that +the @kbd{C-v} or @kbd{M-v} commands leave is controlled by the +variable @code{next-screen-context-lines}; by default, it is 2. The +function keys @key{NEXT} and @key{PRIOR}, or @key{PAGEDOWN} and +@key{PAGEUP}, are equivalent to @kbd{C-v} and @kbd{M-v}. + + The commands @kbd{C-v} and @kbd{M-v} with a numeric argument scroll +the text in the selected window up or down a few lines. @kbd{C-v} +with an argument moves the text and point up, together, that many +lines; it brings the same number of new lines into view at the bottom +of the window. @kbd{M-v} with numeric argument scrolls the text +downward, bringing that many new lines into view at the top of the +window. @kbd{C-v} with a negative argument is like @kbd{M-v} and vice +versa. + + The names of scroll commands are based on the direction that the +text moves in the window. Thus, the command to scroll forward is +called @code{scroll-up} because it moves the text upward on the +screen. The keys @key{PAGEDOWN} and @key{PAGEUP} derive their names +and customary meanings from a different convention that developed +elsewhere; hence the strange result that @key{PAGEDOWN} runs +@code{scroll-up}. + +@vindex scroll-preserve-screen-position + Some users like the full-screen scroll commands to keep point at the +same screen line. To enable this behavior, set the variable +@code{scroll-preserve-screen-position} to a non-@code{nil} value. In +this mode, when these commands would scroll the text around point off +the screen, or within @code{scroll-margin} lines of the edge, they +move point to keep the same vertical position within the window. +This mode is convenient for browsing through a file by scrolling by +screenfuls; if you come back to the screen where you started, point +goes back to the line where it started. However, this mode is +inconvenient when you move to the next screen in order to move point +to the text there. + + Another way to do scrolling is with @kbd{C-l} with a numeric argument. +@kbd{C-l} does not clear the screen when given an argument; it only scrolls +the selected window. With a positive argument @var{n}, it repositions text +to put point @var{n} lines down from the top. An argument of zero puts +point on the very top line. Point does not move with respect to the text; +rather, the text and point move rigidly on the screen. @kbd{C-l} with a +negative argument puts point that many lines from the bottom of the window. +For example, @kbd{C-u - 1 C-l} puts point on the bottom line, and @kbd{C-u +- 5 C-l} puts it five lines from the bottom. @kbd{C-u C-l} scrolls to put +point at the center (vertically) of the selected window. + +@kindex C-M-l +@findex reposition-window + The @kbd{C-M-l} command (@code{reposition-window}) scrolls the current +window heuristically in a way designed to get useful information onto +the screen. For example, in a Lisp file, this command tries to get the +entire current defun onto the screen if possible. + +@node Auto Scrolling +@section Automatic Scrolling + +@vindex scroll-conservatively + Redisplay scrolls the buffer automatically when point moves out of +the visible portion of the text. The purpose of automatic scrolling +is to make point visible, but you can customize many aspects of how +this is done. + + Normally, automatic scrolling centers point vertically within the +window. However, if you set @code{scroll-conservatively} to a small +number @var{n}, then if you move point just a little off the +screen---less than @var{n} lines---then Emacs scrolls the text just +far enough to bring point back on screen. By default, +@code{scroll-conservatively} is@tie{}0. + +@cindex aggressive scrolling +@vindex scroll-up-aggressively +@vindex scroll-down-aggressively + When the window does scroll by a longer distance, you can control +how aggressively it scrolls, by setting the variables +@code{scroll-up-aggressively} and @code{scroll-down-aggressively}. +The value of @code{scroll-up-aggressively} should be either +@code{nil}, or a fraction @var{f} between 0 and 1. A fraction +specifies where on the screen to put point when scrolling upward. +More precisely, when a window scrolls up because point is above the +window start, the new start position is chosen to put point @var{f} +part of the window height from the top. The larger @var{f}, the more +aggressive the scrolling. + + @code{nil}, which is the default, scrolls to put point at the center. +So it is equivalent to .5. + + Likewise, @code{scroll-down-aggressively} is used for scrolling +down. The value, @var{f}, specifies how far point should be placed +from the bottom of the window; thus, as with +@code{scroll-up-aggressively}, a larger value is more aggressive. + +@vindex scroll-margin + The variable @code{scroll-margin} restricts how close point can come +to the top or bottom of a window. Its value is a number of screen +lines; if point comes within that many lines of the top or bottom of the +window, Emacs recenters the window. By default, @code{scroll-margin} is +0. + +@node Horizontal Scrolling +@section Horizontal Scrolling +@cindex horizontal scrolling + + @dfn{Horizontal scrolling} means shifting all the lines sideways +within a window---so that some of the text near the left margin is not +displayed at all. When the text in a window is scrolled horizontally, +text lines are truncated rather than continued (@pxref{Line +Truncation}). Whenever a window shows truncated lines, Emacs +automatically updates its horizontal scrolling whenever point moves +off the left or right edge of the screen. You can also use these +commands to do explicit horizontal scrolling. + +@table @kbd +@item C-x < +Scroll text in current window to the left (@code{scroll-left}). +@item C-x > +Scroll to the right (@code{scroll-right}). +@end table + +@kindex C-x < +@kindex C-x > +@findex scroll-left +@findex scroll-right + The command @kbd{C-x <} (@code{scroll-left}) scrolls the selected +window to the left by @var{n} columns with argument @var{n}. This moves +part of the beginning of each line off the left edge of the window. +With no argument, it scrolls by almost the full width of the window (two +columns less, to be precise). + + @kbd{C-x >} (@code{scroll-right}) scrolls similarly to the right. The +window cannot be scrolled any farther to the right once it is displayed +normally (with each line starting at the window's left margin); +attempting to do so has no effect. This means that you don't have to +calculate the argument precisely for @w{@kbd{C-x >}}; any sufficiently large +argument will restore the normal display. + + If you use those commands to scroll a window horizontally, that sets +a lower bound for automatic horizontal scrolling. Automatic scrolling +will continue to scroll the window, but never farther to the right +than the amount you previously set by @code{scroll-left}. + +@vindex hscroll-margin + The value of the variable @code{hscroll-margin} controls how close +to the window's edges point is allowed to get before the window will +be automatically scrolled. It is measured in columns. If the value +is 5, then moving point within 5 columns of the edge causes horizontal +scrolling away from that edge. + +@vindex hscroll-step + The variable @code{hscroll-step} determines how many columns to +scroll the window when point gets too close to the edge. If it's +zero, horizontal scrolling centers point horizontally within the +window. If it's a positive integer, it specifies the number of +columns to scroll by. If it's a floating-point number, it specifies +the fraction of the window's width to scroll by. The default is zero. + +@vindex auto-hscroll-mode + To disable automatic horizontal scrolling, set the variable +@code{auto-hscroll-mode} to @code{nil}. + +@node Follow Mode +@section Follow Mode +@cindex Follow mode +@cindex mode, Follow +@findex follow-mode +@cindex windows, synchronizing +@cindex synchronizing windows + + @dfn{Follow mode} is a minor mode that makes two windows, both +showing the same buffer, scroll as a single tall ``virtual window.'' +To use Follow mode, go to a frame with just one window, split it into +two side-by-side windows using @kbd{C-x 3}, and then type @kbd{M-x +follow-mode}. From then on, you can edit the buffer in either of the +two windows, or scroll either one; the other window follows it. + + In Follow mode, if you move point outside the portion visible in one +window and into the portion visible in the other window, that selects +the other window---again, treating the two as if they were parts of +one large window. + + To turn off Follow mode, type @kbd{M-x follow-mode} a second time. + +@node Faces +@section Faces: Controlling Text Display Style +@cindex faces + + You can specify various styles for displaying text using +@dfn{faces}. Each face can specify various @dfn{face attributes}, +such as the font family, the height, weight and slant of the +characters, the foreground and background color, and underlining or +overlining. A face does not have to specify all of these attributes; +often it inherits most of them from another face. + + On graphical display, all the Emacs face attributes are meaningful. +On a text-only terminal, only some of them work. Some text-only +terminals support inverse video, bold, and underline attributes; some +support colors. Text-only terminals generally do not support changing +the height and width or the font family. + + Most major modes assign faces to the text automatically through the +work of Font Lock mode. @xref{Font Lock}, for more information about +Font Lock mode and syntactic highlighting. You can print the current +buffer with the highlighting that appears on your screen using the +command @code{ps-print-buffer-with-faces}. @xref{PostScript}. + + You control the appearance of a part of the text in the buffer by +specifying the face or faces to use for it. The style of display used +for any given character is determined by combining the attributes of +all the applicable faces specified for that character. Any attribute +that isn't specified by these faces is taken from the @code{default} face, +whose attributes reflect the default settings of the frame itself. + + Enriched mode, the mode for editing formatted text, includes several +commands and menus for specifying faces for text in the buffer. +@xref{Format Faces}, for how to specify the font for text in the +buffer. @xref{Format Colors}, for how to specify the foreground and +background color. + +@cindex face colors, setting +@findex set-face-foreground +@findex set-face-background + To alter the appearance of a face, use the customization buffer. +@xref{Face Customization}. You can also use X resources to specify +attributes of particular faces (@pxref{Resources}). Alternatively, +you can change the foreground and background colors of a specific face +with @kbd{M-x set-face-foreground} and @kbd{M-x set-face-background}. +These commands prompt in the minibuffer for a face name and a color +name, with completion, and then set that face to use the specified +color. Changing the colors of the @code{default} face also changes +the foreground and background colors on all frames, both existing and +those to be created in the future. (You can also set foreground and +background colors for the current frame only; see @ref{Frame +Parameters}.) + + If you want to alter the appearance of all Emacs frames, you need to +customize the frame parameters in the variable +@code{default-frame-alist}; see @ref{Creating Frames, +default-frame-alist}. + + Emacs can correctly display variable-width fonts, but Emacs commands +that calculate width and indentation do not know how to calculate +variable widths. This can sometimes lead to incorrect results when +you use variable-width fonts. In particular, indentation commands can +give inconsistent results, so we recommend you avoid variable-width +fonts for editing program source code. Filling will sometimes make +lines too long or too short. We plan to address these issues in +future Emacs versions. + +@node Standard Faces +@section Standard Faces + +@findex list-faces-display + To see what faces are currently defined, and what they look like, +type @kbd{M-x list-faces-display}. It's possible for a given face to +look different in different frames; this command shows the appearance +in the frame in which you type it. With a prefix argument, this +prompts for a regular expression, and displays only faces with names +matching that regular expression. + + Here are the standard faces for specifying text appearance. You can +apply them to specific text when you want the effects they produce. + +@table @code +@item default +This face is used for ordinary text that doesn't specify any face. +@item bold +This face uses a bold variant of the default font, if it has one. +It's up to you to choose a default font that has a bold variant, +if you want to use one. +@item italic +This face uses an italic variant of the default font, if it has one. +@item bold-italic +This face uses a bold italic variant of the default font, if it has one. +@item underline +This face underlines text. +@item fixed-pitch +This face forces use of a particular fixed-width font. +@item variable-pitch +This face forces use of a particular variable-width font. It's +reasonable to customize this face to use a different variable-width font, +if you like, but you should not make it a fixed-width font. +@item shadow +This face is used for making the text less noticeable than the surrounding +ordinary text. Usually this can be achieved by using shades of gray in +contrast with either black or white default foreground color. +@end table + + Here's an incomplete list of faces used to highlight parts of the +text temporarily for specific purposes. (Many other modes define +their own faces for this purpose.) + +@table @code +@item highlight +This face is used for highlighting portions of text, in various modes. +For example, mouse-sensitive text is highlighted using this face. +@item isearch +This face is used for highlighting the current Isearch match. +@item query-replace +This face is used for highlighting the current Query Replace match. +@item lazy-highlight +This face is used for lazy highlighting of Isearch and Query Replace +matches other than the current one. +@item region +This face is used for displaying a selected region (when Transient Mark +mode is enabled---see below). +@item secondary-selection +This face is used for displaying a secondary X selection (@pxref{Secondary +Selection}). +@item trailing-whitespace +The face for highlighting excess spaces and tabs at the end of a line +when @code{show-trailing-whitespace} is non-@code{nil}; see +@ref{Useless Whitespace}. +@item nobreak-space +The face for displaying the character ``nobreak space.'' +@item escape-glyph +The face for highlighting the @samp{\} or @samp{^} that indicates +a control character. It's also used when @samp{\} indicates a +nobreak space or nobreak (soft) hyphen. +@end table + +@cindex @code{region} face + When Transient Mark mode is enabled, the text of the region is +highlighted when the mark is active. This uses the face named +@code{region}; you can control the style of highlighting by changing the +style of this face (@pxref{Face Customization}). @xref{Transient Mark}, +for more information about Transient Mark mode and activation and +deactivation of the mark. + + These faces control the appearance of parts of the Emacs frame. +They exist as faces to provide a consistent way to customize the +appearance of these parts of the frame. + +@table @code +@item mode-line +@itemx modeline +This face is used for the mode line of the currently selected window, +and for menu bars when toolkit menus are not used. By default, it's +drawn with shadows for a ``raised'' effect on graphical displays, and +drawn as the inverse of the default face on non-windowed terminals. +@code{modeline} is an alias for the @code{mode-line} face, for +compatibility with old Emacs versions. +@item mode-line-inactive +Like @code{mode-line}, but used for mode lines of the windows other +than the selected one (if @code{mode-line-in-non-selected-windows} is +non-@code{nil}). This face inherits from @code{mode-line}, so changes +in that face affect mode lines in all windows. +@item mode-line-highlight +Like @code{highlight}, but used for portions of text on mode lines. +@item mode-line-buffer-id +This face is used for buffer identification parts in the mode line. +@item header-line +Similar to @code{mode-line} for a window's header line, which appears +at the top of a window just as the mode line appears at the bottom. +Most windows do not have a header line---only some special modes, such +Info mode, create one. +@item vertical-border +This face is used for the vertical divider between windows. +By default this face inherits from the @code{mode-line-inactive} face +on character terminals. On graphical displays the foreground color of +this face is used for the vertical line between windows without +scrollbars. +@item minibuffer-prompt +@cindex @code{minibuffer-prompt} face +@vindex minibuffer-prompt-properties +This face is used for the prompt strings displayed in the minibuffer. +By default, Emacs automatically adds this face to the value of +@code{minibuffer-prompt-properties}, which is a list of text +properties used to display the prompt text. (This variable takes +effect when you enter the minibuffer.) +@item fringe +@cindex @code{fringe} face +The face for the fringes to the left and right of windows on graphic +displays. (The fringes are the narrow portions of the Emacs frame +between the text area and the window's right and left borders.) +@xref{Fringes}. +@item scroll-bar +This face determines the visual appearance of the scroll bar. +@xref{Scroll Bars}. +@item border +This face determines the color of the frame border. +@item cursor +This face determines the color of the cursor. +@item mouse +This face determines the color of the mouse pointer. +@item tool-bar +This face determines the color of tool bar icons. @xref{Tool Bars}. +@item tooltip +This face is used for tooltips. @xref{Tooltips}. +@item menu +@cindex menu bar appearance +@cindex @code{menu} face, no effect if customized +@cindex customization of @code{menu} face +This face determines the colors and font of Emacs's menus. @xref{Menu +Bars}. Setting the font of LessTif/Motif menus is currently not +supported; attempts to set the font are ignored in this case. +Likewise, attempts to customize this face in Emacs built with GTK and +in the MS-Windows/Mac ports are ignored by the respective GUI toolkits; +you need to use system-wide styles and options to change the +appearance of the menus. +@end table + +@node Font Lock +@section Font Lock mode +@cindex Font Lock mode +@cindex mode, Font Lock +@cindex syntax highlighting and coloring + + Font Lock mode is a minor mode, always local to a particular buffer, +which highlights (or ``fontifies'') the buffer contents according to +the syntax of the text you are editing. It can recognize comments and +strings in most languages; in several languages, it can also recognize +and properly highlight various other important constructs---for +example, names of functions being defined or reserved keywords. +Some special modes, such as Occur mode and Info mode, have completely +specialized ways of assigning fonts for Font Lock mode. + +@findex font-lock-mode + Font Lock mode is turned on by default in all modes which support it. +You can toggle font-lock for each buffer with the command @kbd{M-x +font-lock-mode}. Using a positive argument unconditionally turns Font +Lock mode on, and a negative or zero argument turns it off. + +@findex global-font-lock-mode +@vindex global-font-lock-mode + If you do not wish Font Lock mode to be turned on by default, +customize the variable @code{global-font-lock-mode} using the Customize +interface (@pxref{Easy Customization}), or use the function +@code{global-font-lock-mode} in your @file{.emacs} file, like this: + +@example +(global-font-lock-mode 0) +@end example + +@noindent +This variable, like all the variables that control Font Lock mode, +take effect whenever fontification is done; that is, potentially at +any time. + +@findex turn-on-font-lock + If you have disabled Global Font Lock mode, you can still enable Font +Lock for specific major modes by adding the function +@code{turn-on-font-lock} to the mode hooks (@pxref{Hooks}). For +example, to enable Font Lock mode for editing C files, you can do this: + +@example +(add-hook 'c-mode-hook 'turn-on-font-lock) +@end example + + Font Lock mode uses several specifically named faces to do its job, +including @code{font-lock-string-face}, @code{font-lock-comment-face}, +and others. The easiest way to find them all is to use @kbd{M-x +customize-group @key{RET} font-lock-faces @key{RET}}. You can then +use that customization buffer to customize the appearance of these +faces. @xref{Face Customization}. + + You can also customize these faces using @kbd{M-x +set-face-foreground} or @kbd{M-x set-face-background}. @xref{Faces}. + +@vindex font-lock-maximum-decoration + The variable @code{font-lock-maximum-decoration} specifies the +preferred level of fontification, for modes that provide multiple +levels. Level 1 is the least amount of fontification; some modes +support levels as high as 3. The normal default is ``as high as +possible.'' You can specify an integer, which applies to all modes, or +you can specify different numbers for particular major modes; for +example, to use level 1 for C/C++ modes, and the default level +otherwise, use this: + +@example +(setq font-lock-maximum-decoration + '((c-mode . 1) (c++-mode . 1))) +@end example + +@vindex font-lock-maximum-size + Fontification can be too slow for large buffers, so you can suppress +it for buffers above a certain size. The variable +@code{font-lock-maximum-size} specifies a buffer size, beyond which +buffer fontification is suppressed. + +@c @w is used below to prevent a bad page-break. +@vindex font-lock-beginning-of-syntax-function +@cindex incorrect fontification +@cindex parenthesis in column zero and fontification +@cindex brace in column zero and fontification + Comment and string fontification (or ``syntactic'' fontification) +relies on analysis of the syntactic structure of the buffer text. For +the sake of speed, some modes, including Lisp mode, rely on a special +convention: an open-parenthesis or open-brace in the leftmost column +always defines the @w{beginning} of a defun, and is thus always +outside any string or comment. (@xref{Left Margin Paren}.) If you +don't follow this convention, Font Lock mode can misfontify the text +that follows an open-parenthesis or open-brace in the leftmost column +that is inside a string or comment. + +@cindex slow display during scrolling + The variable @code{font-lock-beginning-of-syntax-function} (always +buffer-local) specifies how Font Lock mode can find a position +guaranteed to be outside any comment or string. In modes which use the +leftmost column parenthesis convention, the default value of the variable +is @code{beginning-of-defun}---that tells Font Lock mode to use the +convention. If you set this variable to @code{nil}, Font Lock no longer +relies on the convention. This avoids incorrect results, but the price +is that, in some cases, fontification for a changed text must rescan +buffer text from the beginning of the buffer. This can considerably +slow down redisplay while scrolling, particularly if you are close to +the end of a large buffer. + +@findex font-lock-add-keywords + Font Lock highlighting patterns already exist for many modes, but you +may want to fontify additional patterns. You can use the function +@code{font-lock-add-keywords}, to add your own highlighting patterns for +a particular mode. For example, to highlight @samp{FIXME:} words in C +comments, use this: + +@example +(font-lock-add-keywords + 'c-mode + '(("\\<\\(FIXME\\):" 1 font-lock-warning-face t))) +@end example + +@findex font-lock-remove-keywords + To remove keywords from the font-lock highlighting patterns, use the +function @code{font-lock-remove-keywords}. @xref{Search-based +Fontification,,, elisp, The Emacs Lisp Reference Manual}, for +documentation of the format of this list. + +@cindex just-in-time (JIT) font-lock +@cindex background syntax highlighting + Fontifying large buffers can take a long time. To avoid large +delays when a file is visited, Emacs fontifies only the visible +portion of a buffer. As you scroll through the buffer, each portion +that becomes visible is fontified as soon as it is displayed. The +parts of the buffer that are not displayed are fontified +``stealthily,'' in the background, i.e.@: when Emacs is idle. You can +control this background fontification, also called @dfn{Just-In-Time} +(or @dfn{JIT}) Lock, by customizing variables in the customization +group @samp{jit-lock}. @xref{Specific Customization}. + +@node Highlight Interactively +@section Interactive Highlighting +@cindex highlighting by matching +@cindex interactive highlighting +@cindex Highlight Changes mode + +@findex highlight-changes-mode + Use @kbd{M-x highlight-changes-mode} to enable (or disable) +Highlight Changes mode, a minor mode that uses faces (colors, +typically) to indicate which parts of the buffer were changed most +recently. + +@cindex Hi Lock mode +@findex hi-lock-mode + Hi Lock mode highlights text that matches regular expressions you +specify. For example, you might wish to see all the references to a +certain variable in a program source file, highlight certain parts in +a voluminous output of some program, or make certain names stand out +in an article. Use the @kbd{M-x hi-lock-mode} command to enable (or +disable) Hi Lock mode. To enable Hi Lock mode for all buffers, use +@kbd{M-x global-hi-lock-mode} or place @code{(global-hi-lock-mode 1)} +in your @file{.emacs} file. + + Hi Lock mode works like Font Lock mode (@pxref{Font Lock}), except +that you specify explicitly the regular expressions to highlight. You +control them with these commands: + +@table @kbd +@item C-x w h @var{regexp} @key{RET} @var{face} @key{RET} +@kindex C-x w h +@findex highlight-regexp +Highlight text that matches @var{regexp} using face @var{face} +(@code{highlight-regexp}). The highlighting will remain as long as +the buffer is loaded. For example, to highlight all occurrences of +the word ``whim'' using the default face (a yellow background) +@kbd{C-x w h whim @key{RET} @key{RET}}. Any face can be used for +highlighting, Hi Lock provides several of its own and these are +pre-loaded into a history list. While being prompted for a face use +@kbd{M-p} and @kbd{M-n} to cycle through them. + +You can use this command multiple times, specifying various regular +expressions to highlight in different ways. + +@item C-x w r @var{regexp} @key{RET} +@kindex C-x w r +@findex unhighlight-regexp +Unhighlight @var{regexp} (@code{unhighlight-regexp}). + +If you invoke this from the menu, you select the expression to +unhighlight from a list. If you invoke this from the keyboard, you +use the minibuffer. It will show the most recently added regular +expression; use @kbd{M-p} to show the next older expression and +@kbd{M-n} to select the next newer expression. (You can also type the +expression by hand, with completion.) When the expression you want to +unhighlight appears in the minibuffer, press @kbd{@key{RET}} to exit +the minibuffer and unhighlight it. + +@item C-x w l @var{regexp} @key{RET} @var{face} @key{RET} +@kindex C-x w l +@findex highlight-lines-matching-regexp +@cindex lines, highlighting +@cindex highlighting lines of text +Highlight entire lines containing a match for @var{regexp}, using face +@var{face} (@code{highlight-lines-matching-regexp}). + +@item C-x w b +@kindex C-x w b +@findex hi-lock-write-interactive-patterns +Insert all the current highlighting regexp/face pairs into the buffer +at point, with comment delimiters to prevent them from changing your +program. (This key binding runs the +@code{hi-lock-write-interactive-patterns} command.) + +These patterns are extracted from the comments, if appropriate, if you +invoke @kbd{M-x hi-lock-find-patterns}, or if you visit the file while +Hi Lock mode is enabled (since that runs @code{hi-lock-find-patterns}). + +@item C-x w i +@kindex C-x w i +@findex hi-lock-find-patterns +Extract regexp/face pairs from comments in the current buffer +(@code{hi-lock-find-patterns}). Thus, you can enter patterns +interactively with @code{highlight-regexp}, store them into the file +with @code{hi-lock-write-interactive-patterns}, edit them (perhaps +including different faces for different parenthesized parts of the +match), and finally use this command (@code{hi-lock-find-patterns}) to +have Hi Lock highlight the edited patterns. + +@vindex hi-lock-file-patterns-policy +The variable @code{hi-lock-file-patterns-policy} controls whether Hi +Lock mode should automatically extract and highlight patterns found in +a file when it is visited. Its value can be @code{nil} (never +highlight), @code{t} (highlight the patterns), @code{ask} (query the +user), or a function. If it is a function, +@code{hi-lock-find-patterns} calls it with the patterns as argument; +if the function returns non-@code{nil}, the patterns are used. The +default is @code{nil}. Note that patterns are always highlighted if +you call @code{hi-lock-find-patterns} directly, regardless of the +value of this variable. + +@vindex hi-lock-exclude-modes +Also, @code{hi-lock-find-patterns} does nothing if the current major +mode's symbol is a member of the list @code{hi-lock-exclude-modes}. +@end table + +@node Fringes +@section Window Fringes +@cindex fringes + + On a graphical display, each Emacs window normally has narrow +@dfn{fringes} on the left and right edges. The fringes display +indications about the text in the window. + + The most common use of the fringes is to indicate a continuation +line, when one line of text is split into multiple lines on the +screen. The left fringe shows a curving arrow for each screen line +except the first, indicating that ``this is not the real beginning.'' +The right fringe shows a curving arrow for each screen line except the +last, indicating that ``this is not the real end.'' + + The fringes indicate line truncation with short horizontal arrows +meaning ``there's more text on this line which is scrolled +horizontally out of view;'' clicking the mouse on one of the arrows +scrolls the display horizontally in the direction of the arrow. The +fringes can also indicate other things, such as empty lines, or where a +program you are debugging is executing (@pxref{Debuggers}). + +@findex set-fringe-style +@findex fringe-mode + You can enable and disable the fringes for all frames using +@kbd{M-x fringe-mode}. To enable and disable the fringes +for the selected frame, use @kbd{M-x set-fringe-style}. + +@node Displaying Boundaries +@section Displaying Boundaries + +@vindex indicate-buffer-boundaries + On a graphical display, Emacs can indicate the buffer boundaries in +the fringes. It indicates the first line and the last line with +angle images in the fringes. This can be combined with up and down +arrow images which say whether it is possible to scroll the window up +and down. + + The buffer-local variable @code{indicate-buffer-boundaries} controls +how the buffer boundaries and window scrolling is indicated in the +fringes. If the value is @code{left} or @code{right}, both angle and +arrow bitmaps are displayed in the left or right fringe, respectively. + + If value is an alist, each element @code{(@var{indicator} . +@var{position})} specifies the position of one of the indicators. +The @var{indicator} must be one of @code{top}, @code{bottom}, +@code{up}, @code{down}, or @code{t} which specifies the default +position for the indicators not present in the alist. +The @var{position} is one of @code{left}, @code{right}, or @code{nil} +which specifies not to show this indicator. + + For example, @code{((top . left) (t . right))} places the top angle +bitmap in left fringe, the bottom angle bitmap in right fringe, and +both arrow bitmaps in right fringe. To show just the angle bitmaps in +the left fringe, but no arrow bitmaps, use @code{((top . left) +(bottom . left))}. + +@vindex default-indicate-buffer-boundaries + The value of the variable @code{default-indicate-buffer-boundaries} +is the default value for @code{indicate-buffer-boundaries} in buffers +that do not override it. + +@node Useless Whitespace +@section Useless Whitespace + +@cindex trailing whitespace +@cindex whitespace, trailing +@vindex show-trailing-whitespace + It is easy to leave unnecessary spaces at the end of a line, or +empty lines at the end of a file, without realizing it. In most +cases, this @dfn{trailing whitespace} has no effect, but there are +special circumstances where it matters. It can also be a nuisance +that the line has ``changed,'' when the change is just spaces added or +removed at the end. + + You can make trailing whitespace at the end of a line visible on the +screen by setting the buffer-local variable +@code{show-trailing-whitespace} to @code{t}. Then Emacs displays +trailing whitespace in the face @code{trailing-whitespace}. + + This feature does not apply when point is at the end of the line +containing the whitespace. Strictly speaking, that is ``trailing +whitespace'' nonetheless, but displaying it specially in that case +looks ugly while you are typing in new text. In this special case, +the location of point is enough to show you that the spaces are +present. + +@findex delete-trailing-whitespace + To delete all trailing whitespace within the current buffer's +accessible portion (@pxref{Narrowing}), type @kbd{M-x +delete-trailing-whitespace @key{RET}}. (This command does not remove +the form-feed characters.) + +@vindex indicate-empty-lines +@vindex default-indicate-empty-lines +@cindex unused lines +@cindex fringes, and unused line indication + Emacs can indicate unused lines at the end of the window with a +small image in the left fringe (@pxref{Fringes}). The image appears +for window lines that do not correspond to any buffer text. Blank +lines at the end of the buffer then stand out because they do not have +this image in the fringe. + + To enable this feature, set the buffer-local variable +@code{indicate-empty-lines} to a non-@code{nil} value. The default +value of this variable is controlled by the variable +@code{default-indicate-empty-lines}; by setting that variable, you +can enable or disable this feature for all new buffers. (This feature +currently doesn't work on text-only terminals.) + +@node Selective Display +@section Selective Display +@cindex selective display +@findex set-selective-display +@kindex C-x $ + + Emacs has the ability to hide lines indented more than a certain number +of columns (you specify how many columns). You can use this to get an +overview of a part of a program. + + To hide lines in the current buffer, type @kbd{C-x $} +(@code{set-selective-display}) with a numeric argument @var{n}. Then +lines with at least @var{n} columns of indentation disappear from the +screen. The only indication of their presence is that three dots +(@samp{@dots{}}) appear at the end of each visible line that is +followed by one or more hidden ones. + + The commands @kbd{C-n} and @kbd{C-p} move across the hidden lines as +if they were not there. + + The hidden lines are still present in the buffer, and most editing +commands see them as usual, so you may find point in the middle of the +hidden text. When this happens, the cursor appears at the end of the +previous line, after the three dots. If point is at the end of the +visible line, before the newline that ends it, the cursor appears before +the three dots. + + To make all lines visible again, type @kbd{C-x $} with no argument. + +@vindex selective-display-ellipses + If you set the variable @code{selective-display-ellipses} to +@code{nil}, the three dots do not appear at the end of a line that +precedes hidden lines. Then there is no visible indication of the +hidden lines. This variable becomes local automatically when set. + + See also @ref{Outline Mode} for another way to hide part of +the text in a buffer. + +@node Optional Mode Line +@section Optional Mode Line Features + +@cindex buffer size display +@cindex display of buffer size +@findex size-indication-mode + The buffer percentage @var{pos} indicates the percentage of the +buffer above the top of the window. You can additionally display the +size of the buffer by typing @kbd{M-x size-indication-mode} to turn on +Size Indication mode. The size will be displayed immediately +following the buffer percentage like this: + +@example +@var{POS} of @var{SIZE} +@end example + +@noindent +Here @var{SIZE} is the human readable representation of the number of +characters in the buffer, which means that @samp{k} for 10^3, @samp{M} +for 10^6, @samp{G} for 10^9, etc., are used to abbreviate. + +@cindex narrowing, and buffer size display + If you have narrowed the buffer (@pxref{Narrowing}), the size of the +accessible part of the buffer is shown. + +@cindex line number display +@cindex display of line number +@findex line-number-mode + The current line number of point appears in the mode line when Line +Number mode is enabled. Use the command @kbd{M-x line-number-mode} to +turn this mode on and off; normally it is on. The line number appears +after the buffer percentage @var{pos}, with the letter @samp{L} to +indicate what it is. + +@cindex Column Number mode +@cindex mode, Column Number +@findex column-number-mode + Similarly, you can display the current column number by turning on +Column number mode with @kbd{M-x column-number-mode}. The column +number is indicated by the letter @samp{C}. However, when both of +these modes are enabled, the line and column numbers are displayed in +parentheses, the line number first, rather than with @samp{L} and +@samp{C}. For example: @samp{(561,2)}. @xref{Minor Modes}, for more +information about minor modes and about how to use these commands. + +@cindex narrowing, and line number display + If you have narrowed the buffer (@pxref{Narrowing}), the displayed +line number is relative to the accessible portion of the buffer. +Thus, it isn't suitable as an argument to @code{goto-line}. (Use +@code{what-line} command to see the line number relative to the whole +file.) + +@vindex line-number-display-limit + If the buffer is very large (larger than the value of +@code{line-number-display-limit}), then the line number doesn't appear. +Emacs doesn't compute the line number when the buffer is large, because +that would be too slow. Set it to @code{nil} to remove the limit. + +@vindex line-number-display-limit-width + Line-number computation can also be slow if the lines in the buffer +are too long. For this reason, Emacs normally doesn't display line +numbers if the average width, in characters, of lines near point is +larger than the value of the variable +@code{line-number-display-limit-width}. The default value is 200 +characters. + +@findex display-time +@cindex time (on mode line) + Emacs can optionally display the time and system load in all mode +lines. To enable this feature, type @kbd{M-x display-time} or customize +the option @code{display-time-mode}. The information added to the mode +line usually appears after the buffer name, before the mode names and +their parentheses. It looks like this: + +@example +@var{hh}:@var{mm}pm @var{l.ll} +@end example + +@noindent +@vindex display-time-24hr-format +Here @var{hh} and @var{mm} are the hour and minute, followed always by +@samp{am} or @samp{pm}. @var{l.ll} is the average number of running +processes in the whole system recently. (Some fields may be missing if +your operating system cannot support them.) If you prefer time display +in 24-hour format, set the variable @code{display-time-24hr-format} +to @code{t}. + +@cindex mail (on mode line) +@vindex display-time-use-mail-icon +@vindex display-time-mail-face +@vindex display-time-mail-file +@vindex display-time-mail-directory + The word @samp{Mail} appears after the load level if there is mail +for you that you have not read yet. On a graphical display you can use +an icon instead of @samp{Mail} by customizing +@code{display-time-use-mail-icon}; this may save some space on the mode +line. You can customize @code{display-time-mail-face} to make the mail +indicator prominent. Use @code{display-time-mail-file} to specify +the mail file to check, or set @code{display-time-mail-directory} +to specify the directory to check for incoming mail (any nonempty regular +file in the directory is considered as ``newly arrived mail''). + +@cindex mode line, 3D appearance +@cindex attributes of mode line, changing +@cindex non-integral number of lines in a window + By default, the mode line is drawn on graphics displays with +3D-style highlighting, like that of a button when it is not being +pressed. If you don't like this effect, you can disable the 3D +highlighting of the mode line, by customizing the attributes of the +@code{mode-line} face. @xref{Face Customization}. + +@cindex non-selected windows, mode line appearance + By default, the mode line of nonselected windows is displayed in a +different face, called @code{mode-line-inactive}. Only the selected +window is displayed in the @code{mode-line} face. This helps show +which window is selected. When the minibuffer is selected, since +it has no mode line, the window from which you activated the minibuffer +has its mode line displayed using @code{mode-line}; as a result, +ordinary entry to the minibuffer does not change any mode lines. + +@vindex mode-line-in-non-selected-windows + You can disable use of @code{mode-line-inactive} by setting variable +@code{mode-line-in-non-selected-windows} to @code{nil}; then all mode +lines are displayed in the @code{mode-line} face. + +@vindex eol-mnemonic-unix +@vindex eol-mnemonic-dos +@vindex eol-mnemonic-mac +@vindex eol-mnemonic-undecided + You can customize the mode line display for each of the end-of-line +formats by setting each of the variables @code{eol-mnemonic-unix}, +@code{eol-mnemonic-dos}, @code{eol-mnemonic-mac}, and +@code{eol-mnemonic-undecided} to the strings you prefer. + +@node Text Display +@section How Text Is Displayed +@cindex characters (in text) + + @acronym{ASCII} printing characters (octal codes 040 through 0176) in Emacs +buffers are displayed with their graphics, as are non-ASCII multibyte +printing characters (octal codes above 0400). + + Some @acronym{ASCII} control characters are displayed in special ways. The +newline character (octal code 012) is displayed by starting a new line. +The tab character (octal code 011) is displayed by moving to the next +tab stop column (normally every 8 columns). + + Other @acronym{ASCII} control characters are normally displayed as a caret +(@samp{^}) followed by the non-control version of the character; thus, +control-A is displayed as @samp{^A}. The caret appears in face +@code{escape-glyph}. + + Non-@acronym{ASCII} characters 0200 through 0237 (octal) are +displayed with octal escape sequences; thus, character code 0230 +(octal) is displayed as @samp{\230}. The backslash appears in face +@code{escape-glyph}. + +@vindex ctl-arrow + If the variable @code{ctl-arrow} is @code{nil}, control characters in +the buffer are displayed with octal escape sequences, except for newline +and tab. Altering the value of @code{ctl-arrow} makes it local to the +current buffer; until that time, the default value is in effect. The +default is initially @code{t}. + + The display of character codes 0240 through 0377 (octal) may be +either as escape sequences or as graphics. They do not normally occur +in multibyte buffers, but if they do, they are displayed as Latin-1 +graphics. In unibyte mode, if you enable European display they are +displayed using their graphics (assuming your terminal supports them), +otherwise as escape sequences. @xref{Unibyte Mode}. + +@vindex nobreak-char-display +@cindex no-break space, display +@cindex no-break hyphen, display +@cindex soft hyphen, display + Some character sets define ``no-break'' versions of the space and +hyphen characters, which are used where a line should not be broken. +Emacs normally displays these characters with special faces +(respectively, @code{nobreak-space} and @code{escape-glyph}) to +distinguish them from ordinary spaces and hyphens. You can turn off +this feature by setting the variable @code{nobreak-char-display} to +@code{nil}. If you set the variable to any other value, that means to +prefix these characters with an escape character. + +@vindex tab-width +@vindex default-tab-width + Normally, a tab character in the buffer is displayed as whitespace which +extends to the next display tab stop position, and display tab stops come +at intervals equal to eight spaces. The number of spaces per tab is +controlled by the variable @code{tab-width}, which is made local by +changing it. Note that how the tab character +in the buffer is displayed has nothing to do with the definition of +@key{TAB} as a command. The variable @code{tab-width} must have an +integer value between 1 and 1000, inclusive. The variable +@code{default-tab-width} controls the default value of this variable +for buffers where you have not set it locally. + + You can customize the way any particular character code is displayed +by means of a display table. @xref{Display Tables,, Display Tables, +elisp, The Emacs Lisp Reference Manual}. + +@node Cursor Display +@section Displaying the Cursor + +@findex blink-cursor-mode +@vindex blink-cursor-alist +@cindex cursor, locating visually +@cindex cursor, blinking + You can customize the cursor's color, and whether it blinks, using +the @code{cursor} Custom group (@pxref{Easy Customization}). On +a graphical display, the command @kbd{M-x blink-cursor-mode} enables +or disables the blinking of the cursor. (On text terminals, the +terminal itself blinks the cursor, and Emacs has no control over it.) +You can control how the cursor appears when it blinks off by setting +the variable @code{blink-cursor-alist}. + +@vindex visible-cursor + Some text terminals offer two different cursors: the normal cursor +and the very visible cursor, where the latter may be e.g. bigger or +blinking. By default Emacs uses the very visible cursor, and switches +to it when you start or resume Emacs. If the variable +@code{visible-cursor} is @code{nil} when Emacs starts or resumes, it +doesn't switch, so it uses the normal cursor. + +@cindex cursor in non-selected windows +@vindex cursor-in-non-selected-windows + Normally, the cursor appears in non-selected windows in the ``off'' +state, with the same appearance as when the blinking cursor blinks +``off.'' For a box cursor, this is a hollow box; for a bar cursor, +this is a thinner bar. To turn off cursors in non-selected windows, +customize the variable @code{cursor-in-non-selected-windows} and assign +it a @code{nil} value. + +@vindex x-stretch-cursor +@cindex wide block cursor + On graphical displays, Emacs can optionally draw the block cursor +as wide as the character under the cursor---for example, if the cursor +is on a tab character, it would cover the full width occupied by that +tab character. To enable this feature, set the variable +@code{x-stretch-cursor} to a non-@code{nil} value. + +@findex hl-line-mode +@findex global-hl-line-mode +@cindex highlight current line + To make the cursor even more visible, you can use HL Line mode, a +minor mode that highlights the line containing point. Use @kbd{M-x +hl-line-mode} to enable or disable it in the current buffer. @kbd{M-x +global-hl-line-mode} enables or disables the same mode globally. + +@node Line Truncation +@section Truncation of Lines + +@cindex truncation +@cindex line truncation, and fringes + As an alternative to continuation, Emacs can display long lines by +@dfn{truncation}. This means that all the characters that do not fit +in the width of the screen or window do not appear at all. On +graphical displays, a small straight arrow in the fringe indicates +truncation at either end of the line. On text-only terminals, @samp{$} +appears in the first column when there is text truncated to the left, +and in the last column when there is text truncated to the right. + +@vindex truncate-lines +@findex toggle-truncate-lines + Horizontal scrolling automatically causes line truncation +(@pxref{Horizontal Scrolling}). You can explicitly enable line +truncation for a particular buffer with the command @kbd{M-x +toggle-truncate-lines}. This works by locally changing the variable +@code{truncate-lines}. If that variable is non-@code{nil}, long lines +are truncated; if it is @code{nil}, they are continued onto multiple +screen lines. Setting the variable @code{truncate-lines} in any way +makes it local to the current buffer; until that time, the default +value is in effect. The default value is normally @code{nil}. + +@c @vindex truncate-partial-width-windows @c Idx entry is in Split Windows. + If the variable @code{truncate-partial-width-windows} is +non-@code{nil}, it forces truncation rather than continuation in any +window less than the full width of the screen or frame, regardless of +the value of @code{truncate-lines}. For information about side-by-side +windows, see @ref{Split Window}. See also @ref{Display,, Display, +elisp, The Emacs Lisp Reference Manual}. + +@vindex overflow-newline-into-fringe + If the variable @code{overflow-newline-into-fringe} is +non-@code{nil} on a graphical display, then Emacs does not continue or +truncate a line which is exactly as wide as the window. Instead, the +newline overflows into the right fringe, and the cursor appears in the +fringe when positioned on that newline. + +@node Display Custom +@section Customization of Display + + This section describes variables (@pxref{Variables}) that you can +change to customize how Emacs displays. Beginning users can skip +it. +@c the reason for that pxref is because an xref early in the +@c ``echo area'' section leads here. + +@vindex inverse-video + If the variable @code{inverse-video} is non-@code{nil}, Emacs attempts +to invert all the lines of the display from what they normally are. + +@vindex visible-bell + If the variable @code{visible-bell} is non-@code{nil}, Emacs attempts +to make the whole screen blink when it would normally make an audible bell +sound. This variable has no effect if your terminal does not have a way +to make the screen blink. + +@vindex echo-keystrokes + The variable @code{echo-keystrokes} controls the echoing of multi-character +keys; its value is the number of seconds of pause required to cause echoing +to start, or zero, meaning don't echo at all. The value takes effect when +there is someting to echo. @xref{Echo Area}. + +@vindex baud-rate + The variable @anchor{baud-rate}@code{baud-rate} holds the output +speed of the terminal, as far as Emacs knows. Setting this variable +does not change the speed of actual data transmission, but the value +is used for calculations. On text-only terminals, it affects padding, +and decisions about whether to scroll part of the screen or redraw it +instead. It also affects the behavior of incremental search. + + On graphical displays, @code{baud-rate} is only used to determine +how frequently to look for pending input during display updating. A +higher value of @code{baud-rate} means that check for pending input +will be done less frequently. + +@cindex hourglass pointer display +@vindex hourglass-delay + On graphical display, Emacs can optionally display the mouse pointer +in a special shape to say that Emacs is busy. To turn this feature on +or off, customize the group @code{cursor}. You can also control the +amount of time Emacs must remain busy before the busy indicator is +displayed, by setting the variable @code{hourglass-delay}. + +@vindex overline-margin + On graphical display, this variables specifies the vertical position +of an overline above the text, including the height of the overline +itself (1 pixel). The default value is 2 pixels. + +@vindex x-underline-at-descent-line + On graphical display, Emacs normally draws an underline at the +baseline level of the font. If @code{x-underline-at-descent-line} is +non-@code{nil}, Emacs draws the underline at the same height as the +font's descent line. + +@findex tty-suppress-bold-inverse-default-colors + On some text-only terminals, bold face and inverse video together +result in text that is hard to read. Call the function +@code{tty-suppress-bold-inverse-default-colors} with a non-@code{nil} +argument to suppress the effect of bold-face in this case. + +@vindex no-redraw-on-reenter + On a text-only terminal, when you reenter Emacs after suspending, Emacs +normally clears the screen and redraws the entire display. On some +terminals with more than one page of memory, it is possible to arrange +the termcap entry so that the @samp{ti} and @samp{te} strings (output +to the terminal when Emacs is entered and exited, respectively) switch +between pages of memory so as to use one page for Emacs and another +page for other output. On such terminals, you might want to set the variable +@code{no-redraw-on-reenter} non-@code{nil}; this tells Emacs to +assume, when resumed, that the screen page it is using still contains +what Emacs last wrote there. + +@ignore + arch-tag: 2219f910-2ff0-4521-b059-1bd231a536c4 +@end ignore |