@c -*-texinfo-*-
@c This is part of the GNU Emacs Lisp Reference Manual.
-@c Copyright (C) 1990, 1991, 1992, 1993, 1994, 1995, 1998 Free Software Foundation, Inc.
+@c Copyright (C) 1990, 1991, 1992, 1993, 1994, 1995, 1998, 1999, 2002, 2003,
+@c 2004, 2005, 2006 Free Software Foundation, Inc.
@c See the file elisp.texi for copying conditions.
@setfilename ../info/frames
@node Frames, Positions, Windows, Top
@chapter Frames
@cindex frame
- A @dfn{frame} is a rectangle on the screen that contains one or more
-Emacs windows. A frame initially contains a single main window (plus
-perhaps a minibuffer window), which you can subdivide vertically or
-horizontally into smaller windows.
+ In Emacs editing, A @dfn{frame} is a screen object that contains one
+or more Emacs windows. It's the kind of object that is called a
+``window'' in the terminology of graphical environments; but we can't
+call it a ``window'' here, because Emacs uses that word in a different
+way.
+
+ A frame initially contains a single main window and/or a minibuffer
+window; you can subdivide the main window vertically or horizontally
+into smaller windows. In Emacs Lisp, a @dfn{frame object} is a Lisp
+object that represents a frame on the screen.
@cindex terminal frame
-@cindex X window frame
When Emacs runs on a text-only terminal, it starts with one
@dfn{terminal frame}. If you create additional ones, Emacs displays
one and only one at any given time---on the terminal screen, of course.
- When Emacs communicates directly with an X server, it does not have a
-terminal frame; instead, it starts with a single @dfn{X window frame}.
-It can display multiple X window frames at the same time, each in its
-own X window.
+@cindex window frame
+ When Emacs communicates directly with a supported window system, such
+as X, it does not have a terminal frame; instead, it starts with
+a single @dfn{window frame}, but you can create more, and Emacs can
+display several such frames at once as is usual for window systems.
@defun framep object
-This predicate returns @code{t} if @var{object} is a frame, and
-@code{nil} otherwise.
+This predicate returns a non-@code{nil} value if @var{object} is a
+frame, and @code{nil} otherwise. For a frame, the value indicates which
+kind of display the frame uses:
+
+@table @code
+@item x
+The frame is displayed in an X window.
+@item t
+A terminal frame on a character display.
+@item mac
+The frame is displayed on a Macintosh.
+@item w32
+The frame is displayed on MS-Windows 9X/NT.
+@item pc
+The frame is displayed on an MS-DOS terminal.
+@end table
@end defun
@menu
* Creating Frames:: Creating additional frames.
-* Multiple Displays:: Creating frames on other X displays.
+* Multiple Displays:: Creating frames on other displays.
* Frame Parameters:: Controlling frame size, position, font, etc.
* Frame Titles:: Automatic updating of frame titles.
* Deleting Frames:: Frames last until explicitly deleted.
* Minibuffers and Frames:: How a frame finds the minibuffer to use.
* Input Focus:: Specifying the selected frame.
* Visibility of Frames:: Frames may be visible or invisible, or icons.
-* Raising and Lowering:: Raising a frame makes it hide other X windows;
- lowering it makes the others hide them.
+* Raising and Lowering:: Raising a frame makes it hide other windows;
+ lowering it makes the others hide it.
* Frame Configurations:: Saving the state of all frames.
* Mouse Tracking:: Getting events that say when the mouse moves.
* Mouse Position:: Asking where the mouse is, or moving it.
* Pop-Up Menus:: Displaying a menu for the user to select from.
* Dialog Boxes:: Displaying a box to ask yes or no.
-* Pointer Shapes:: Specifying the shape of the mouse pointer.
-* X Selections:: Transferring text to and from other X clients.
-* Font Names:: Looking up font names.
+* Pointer Shape:: Specifying the shape of the mouse pointer.
+* Window System Selections:: Transferring text to and from other X clients.
+* Drag and Drop:: Internals of Drag-and-Drop implementation.
* Color Names:: Getting the definitions of color names.
+* Text Terminal Colors:: Defining colors for text-only terminals.
* Resources:: Getting resource values from the server.
-* Server Data:: Getting info about the X server.
+* Display Feature Testing:: Determining the features of a terminal.
@end menu
- @xref{Display}, for related information.
+ @xref{Display}, for information about the related topic of
+controlling Emacs redisplay.
@node Creating Frames
@section Creating Frames
To create a new frame, call the function @code{make-frame}.
@defun make-frame &optional alist
-This function creates a new frame. If you are using X, it makes
-an X window frame; otherwise, it makes a terminal frame.
+This function creates and returns a new frame, displaying the current
+buffer. If you are using a supported window system, it makes a window
+frame; otherwise, it makes a terminal frame.
The argument is an alist specifying frame parameters. Any parameters
not mentioned in @var{alist} default according to the value of the
variable @code{default-frame-alist}; parameters not specified even there
-default from the standard X defaults file and X resources.
+default from the standard X resources or whatever is used instead on
+your system.
The set of possible parameters depends in principle on what kind of
-window system Emacs uses to display its frames. @xref{X Frame
+window system Emacs uses to display its frames. @xref{Window Frame
Parameters}, for documentation of individual parameters you can specify.
+
+This function itself does not make the new frame the selected frame.
+@xref{Input Focus}. The previously selected frame remains selected.
+However, the window system may select the new frame for its own reasons,
+for instance if the frame appears under the mouse pointer and your
+setup is for focus to follow the pointer.
@end defun
-@tindex before-make-frame-hook
@defvar before-make-frame-hook
A normal hook run by @code{make-frame} before it actually creates the
frame.
@end defvar
-@tindex after-make-frame-hook
-@defvar after-make-frame-hook
+@defvar after-make-frame-functions
An abnormal hook run by @code{make-frame} after it creates the frame.
-Each function in @code{after-make-frame-hook} receives one argument, the
+Each function in @code{after-make-frame-functions} receives one argument, the
frame just created.
@end defvar
@node Multiple Displays
@section Multiple Displays
-@cindex multiple displays
-@cindex multiple X terminals
+@cindex multiple X displays
@cindex displays, multiple
- A single Emacs can talk to more than one X Windows display.
+ A single Emacs can talk to more than one X display.
Initially, Emacs uses just one display---the one chosen with the
@code{DISPLAY} environment variable or with the @samp{--display} option
(@pxref{Initial Options,,, emacs, The GNU Emacs Manual}). To connect to
the @code{display} frame parameter when you create the frame.
Emacs treats each X server as a separate terminal, giving each one its
-own selected frame and its own minibuffer windows. A few Lisp variables
-have values local to the current terminal (that is, the terminal
-corresponding to the currently selected frame): these are
-@code{default-minibuffer-frame}, @code{defining-kbd-macro},
-@code{last-kbd-macro}, and @code{system-key-alist}. These variables are
-always terminal-local and can never be buffer-local.
+own selected frame and its own minibuffer windows. However, only one of
+those frames is ``@emph{the} selected frame'' at any given moment, see
+@ref{Input Focus}.
+
+ A few Lisp variables are @dfn{terminal-local}; that is, they have a
+separate binding for each terminal. The binding in effect at any time
+is the one for the terminal that the currently selected frame belongs
+to. These variables include @code{default-minibuffer-frame},
+@code{defining-kbd-macro}, @code{last-kbd-macro}, and
+@code{system-key-alist}. They are always terminal-local, and can never
+be buffer-local (@pxref{Buffer-Local Variables}) or frame-local.
A single X server can handle more than one screen. A display name
-@samp{@var{host}.@var{server}.@var{screen}} has three parts; the last
+@samp{@var{host}:@var{server}.@var{screen}} has three parts; the last
part specifies the screen number for a given server. When you use two
screens belonging to one server, Emacs knows by the similarity in their
names that they share a single keyboard, and it treats them as a single
terminal.
@deffn Command make-frame-on-display display &optional parameters
-This creates a new frame on display @var{display}, taking the other
-frame parameters from @var{parameters}. Aside from the @var{display}
-argument, it is like @code{make-frame} (@pxref{Creating Frames}).
+This creates and returns a new frame on display @var{display}, taking
+the other frame parameters from @var{parameters}. Aside from the
+@var{display} argument, it is like @code{make-frame} (@pxref{Creating
+Frames}).
@end deffn
@defun x-display-list
a display name.
@end defun
-@defun x-open-connection display &optional xrm-string
+@defun x-open-connection display &optional xrm-string must-succeed
This function opens a connection to the X display @var{display}. It
does not create a frame on that display, but it permits you to check
that communication can be established with that display.
"*BorderWidth: 3\n*InternalBorder: 2\n"
@end example
-@xref{Resources}.
+@xref{X Resources,, X Resources, emacs, The GNU Emacs Manual}.
+
+If @var{must-succeed} is non-@code{nil}, failure to open the connection
+terminates Emacs. Otherwise, it is an ordinary Lisp error.
@end defun
@defun x-close-connection display
@node Frame Parameters
@section Frame Parameters
-A frame has many parameters that control its appearance and behavior.
+ A frame has many parameters that control its appearance and behavior.
Just what parameters a frame has depends on what display mechanism it
uses.
-Frame parameters exist for the sake of window systems. A terminal frame
-has a few parameters, mostly for compatibility's sake; only the height,
-width and @code{buffer-predicate} parameters really do something.
+ Frame parameters exist mostly for the sake of window systems. A
+terminal frame has a few parameters, mostly for compatibility's sake;
+only the @code{height}, @code{width}, @code{name}, @code{title},
+@code{menu-bar-lines}, @code{buffer-list} and @code{buffer-predicate}
+parameters do something special. If the terminal supports colors, the
+parameters @code{foreground-color}, @code{background-color},
+@code{background-mode} and @code{display-type} are also meaningful.
@menu
* Parameter Access:: How to change a frame's parameters.
* Initial Parameters:: Specifying frame parameters when you make a frame.
-* X Frame Parameters:: List of frame parameters.
+* Window Frame Parameters:: List of frame parameters for window systems.
* Size and Position:: Changing the size and position of a frame.
+* Geometry:: Parsing geometry specifications.
@end menu
@node Parameter Access
These functions let you read and change the parameter values of a
frame.
-@defun frame-parameters frame
+@defun frame-parameter frame parameter
+This function returns the value of the parameter @var{parameter} (a
+symbol) of @var{frame}. If @var{frame} is @code{nil}, it returns the
+selected frame's parameter. If @var{frame} has no setting for
+@var{parameter}, this function returns @code{nil}.
+@end defun
+
+@defun frame-parameters &optional frame
The function @code{frame-parameters} returns an alist listing all the
-parameters of @var{frame} and their values.
+parameters of @var{frame} and their values. If @var{frame} is
+@code{nil} or omitted, this returns the selected frame's parameters
@end defun
@defun modify-frame-parameters frame alist
elements of @var{alist}. Each element of @var{alist} has the form
@code{(@var{parm} . @var{value})}, where @var{parm} is a symbol naming a
parameter. If you don't mention a parameter in @var{alist}, its value
-doesn't change.
+doesn't change. If @var{frame} is @code{nil}, it defaults to the selected
+frame.
+@end defun
+
+@defun modify-all-frames-parameters alist
+This function alters the frame parameters of all existing frames
+according to @var{alist}, then modifies @code{default-frame-alist}
+(and, if necessary, @code{initial-frame-alist}) to apply the same
+parameter values to frames that will be created henceforth.
@end defun
@node Initial Parameters
@subsection Initial Frame Parameters
You can specify the parameters for the initial startup frame
-by setting @code{initial-frame-alist} in your @file{.emacs} file.
+by setting @code{initial-frame-alist} in your init file (@pxref{Init File}).
@defvar initial-frame-alist
This variable's value is an alist of parameter values used when creating
-the initial X window frame. You can set this variable to specify the
+the initial window frame. You can set this variable to specify the
appearance of the initial frame without altering subsequent frames.
Each element has the form:
(@var{parameter} . @var{value})
@end example
-Emacs creates the initial frame before it reads your @file{~/.emacs}
+Emacs creates the initial frame before it reads your init
file. After reading that file, Emacs checks @code{initial-frame-alist},
and applies the parameter settings in the altered value to the already
created initial frame.
If these settings affect the frame geometry and appearance, you'll see
the frame appear with the wrong ones and then change to the specified
ones. If that bothers you, you can specify the same geometry and
-appearance with X resources; those do take affect before the frame is
-created. @xref{Resources X,, X Resources, emacs, The GNU Emacs Manual}.
+appearance with X resources; those do take effect before the frame is
+created. @xref{X Resources,, X Resources, emacs, The GNU Emacs Manual}.
X resource settings typically apply to all frames. If you want to
specify some X resources solely for the sake of the initial frame, and
@defvar default-frame-alist
This is an alist specifying default values of frame parameters for all
-Emacs frames---the first frame, and subsequent frames. In many cases,
-you can get the same results by means of X resources.
+Emacs frames---the first frame, and subsequent frames. When using the X
+Window System, you can get the same results by means of X resources
+in many cases.
+
+Setting this variable does not affect existing frames.
@end defvar
-See also @code{special-display-frame-alist}, in @ref{Choosing Window}.
+See also @code{special-display-frame-alist}. @xref{Definition of
+special-display-frame-alist}.
If you use options that specify window appearance when you invoke Emacs,
they take effect by adding elements to @code{default-frame-alist}. One
exception is @samp{-geometry}, which adds the specified position to
-@code{initial-frame-alist} instead. @xref{Command Arguments,,, emacs,
-The GNU Emacs Manual}.
+@code{initial-frame-alist} instead. @xref{Emacs Invocation,, Command
+Line Arguments for Emacs Invocation, emacs, The GNU Emacs Manual}.
-@node X Frame Parameters
-@subsection X Window Frame Parameters
+@node Window Frame Parameters
+@subsection Window Frame Parameters
-Just what parameters a frame has depends on what display mechanism it
-uses. Here is a table of the parameters of an X window frame; of these,
-@code{name}, @code{height}, @code{width}, and @code{buffer-predicate}
-provide meaningful information in non-X frames.
+ Just what parameters a frame has depends on what display mechanism
+it uses. This section describes the parameters that have special
+meanings on some or all kinds of terminals. Of these, @code{name},
+@code{title}, @code{height}, @code{width}, @code{buffer-list} and
+@code{buffer-predicate} provide meaningful information in terminal
+frames, and @code{tty-color-mode} is meaningful @emph{only} in
+terminal frames.
+
+@menu
+* Basic Parameters:: Parameters that are fundamental.
+* Position Parameters:: The position of the frame on the screen.
+* Size Parameters:: Frame's size.
+* Layout Parameters:: Size of parts of the frame, and
+ enabling or disabling some parts.
+* Buffer Parameters:: Which buffers have been or should be shown.
+* Management Parameters:: Communicating with the window manager.
+* Cursor Parameters:: Controlling the cursor appearance.
+* Color Parameters:: Colors of various parts of the frame.
+@end menu
+
+@node Basic Parameters
+@subsubsection Basic Parameters
+
+ These frame parameters give the most basic information about the
+frame. @code{title} and @code{name} are meaningful on all terminals.
@table @code
+@item display
+The display on which to open this frame. It should be a string of the
+form @code{"@var{host}:@var{dpy}.@var{screen}"}, just like the
+@code{DISPLAY} environment variable.
+
+@item display-type
+This parameter describes the range of possible colors that can be used
+in this frame. Its value is @code{color}, @code{grayscale} or
+@code{mono}.
+
+@item title
+If a frame has a non-@code{nil} title, it appears in the window system's
+border for the frame, and also in the mode line of windows in that frame
+if @code{mode-line-frame-identification} uses @samp{%F}
+(@pxref{%-Constructs}). This is normally the case when Emacs is not
+using a window system, and can only display one frame at a time.
+@xref{Frame Titles}.
+
@item name
-The name of the frame. Most window managers display the frame's name in
-the frame's border, at the top of the frame. If you don't specify a
-name, and you have more than one frame, Emacs sets the frame name based
-on the buffer displayed in the frame's selected window.
+The name of the frame. The frame name serves as a default for the frame
+title, if the @code{title} parameter is unspecified or @code{nil}. If
+you don't specify a name, Emacs sets the frame name automatically
+(@pxref{Frame Titles}).
If you specify the frame name explicitly when you create the frame, the
name is also used (instead of the name of the Emacs executable) when
looking up X resources for the frame.
+@end table
-Since a non-window terminal can display only one frame at a time, the
-frame name appears in the mode line.
+@node Position Parameters
+@subsubsection Position Parameters
-@item display
-The display on which to open this frame. It should be a string of the
-form @code{"@var{host}:@var{dpy}.@var{screen}"}, just like the
-@code{DISPLAY} environment variable.
+ Position parameters' values are normally measured in pixels, but on
+text-only terminals they count characters or lines instead.
+@table @code
@item left
The screen position of the left edge, in pixels, with respect to the
left edge of the screen. The value may be a positive number @var{pos},
A negative number @minus{}@var{pos}, or a list of the form @code{(-
@var{pos})}, actually specifies the position of the right edge of the
window with respect to the right edge of the screen. A positive value
-of @var{pos} counts toward the left. If the parameter is a negative
-integer @minus{}@var{pos} then @var{pos} is positive!
+of @var{pos} counts toward the left. @strong{Reminder:} if the
+parameter is a negative integer @minus{}@var{pos}, then @var{pos} is
+positive.
Some window managers ignore program-specified positions. If you want to
be sure the position you specify is not ignored, specify a
@item top
The screen position of the top edge, in pixels, with respect to the
-top edge of the screen. The value may be a positive number @var{pos},
-or a list of the form @code{(+ @var{pos})} which permits specifying a
-negative @var{pos} value.
-
-A negative number @minus{}@var{pos}, or a list of the form @code{(-
-@var{pos})}, actually specifies the position of the bottom edge of the
-window with respect to the bottom edge of the screen. A positive value
-of @var{pos} counts toward the top. If the parameter is a negative
-integer @minus{}@var{pos} then @var{pos} is positive!
-
-Some window managers ignore program-specified positions. If you want to
-be sure the position you specify is not ignored, specify a
-non-@code{nil} value for the @code{user-position} parameter as well.
+top edge of the screen. It works just like @code{left}, except vertically
+instead of horizontally.
@item icon-left
The screen position of the left edge @emph{of the frame's icon}, in
pixels, counting from the left edge of the screen. This takes effect if
and when the frame is iconified.
+If you specify a value for this parameter, then you must also specify
+a value for @code{icon-top} and vice versa. The window manager may
+ignore these two parameters.
+
@item icon-top
The screen position of the top edge @emph{of the frame's icon}, in
pixels, counting from the top edge of the screen. This takes effect if
value for this parameter if the values of the @code{left} and @code{top}
parameters represent the user's stated preference; otherwise, use
@code{nil}.
+@end table
+
+@node Size Parameters
+@subsubsection Size Parameters
+ Size parameters' values are normally measured in pixels, but on
+text-only terminals they count characters or lines instead.
+
+@table @code
@item height
The height of the frame contents, in characters. (To get the height in
pixels, call @code{frame-pixel-height}; see @ref{Size and Position}.)
The width of the frame contents, in characters. (To get the height in
pixels, call @code{frame-pixel-width}; see @ref{Size and Position}.)
-@item window-id
-The number of the X window for the frame.
+@item user-size
+This does for the size parameters @code{height} and @code{width} what
+the @code{user-position} parameter (see above) does for the position
+parameters @code{top} and @code{left}.
+
+@item fullscreen
+Specify that width, height or both shall be set to the size of the screen.
+The value @code{fullwidth} specifies that width shall be the size of the
+screen. The value @code{fullheight} specifies that height shall be the
+size of the screen. The value @code{fullboth} specifies that both the
+width and the height shall be set to the size of the screen.
+@end table
+
+@node Layout Parameters
+@subsubsection Layout Parameters
+
+ These frame parameters enable or disable various parts of the
+frame, or control their sizes.
+
+@table @code
+@item border-width
+The width in pixels of the frame's border.
+
+@item internal-border-width
+The distance in pixels between text (or fringe) and the frame's border.
+
+@item vertical-scroll-bars
+Whether the frame has scroll bars for vertical scrolling, and which side
+of the frame they should be on. The possible values are @code{left},
+@code{right}, and @code{nil} for no scroll bars.
+
+@ignore
+@item horizontal-scroll-bars
+Whether the frame has scroll bars for horizontal scrolling
+(non-@code{nil} means yes). Horizontal scroll bars are not currently
+implemented.
+@end ignore
+
+@item scroll-bar-width
+The width of vertical scroll bars, in pixels, or @code{nil} meaning to
+use the default width.
+
+@item left-fringe
+@itemx right-fringe
+The default width of the left and right fringes of windows in this
+frame (@pxref{Fringes}). If either of these is zero, that effectively
+removes the corresponding fringe. A value of @code{nil} stands for
+the standard fringe width, which is the width needed to display the
+fringe bitmaps.
+
+The combined fringe widths must add up to an integral number of
+columns, so the actual default fringe widths for the frame may be
+larger than the specified values. The extra width needed to reach an
+acceptable total is distributed evenly between the left and right
+fringe. However, you can force one fringe or the other to a precise
+width by specifying that width as a negative integer. If both widths are
+negative, only the left fringe gets the specified width.
+
+@item menu-bar-lines
+The number of lines to allocate at the top of the frame for a menu
+bar. The default is 1. A value of @code{nil} means don't display a
+menu bar. @xref{Menu Bar}. (The X toolkit and GTK allow at most one
+menu bar line; they treat larger values as 1.)
+
+@item tool-bar-lines
+The number of lines to use for the tool bar. A value of @code{nil}
+means don't display a tool bar. (GTK allows at most one tool bar line;
+it treats larger values as 1.)
+
+@item line-spacing
+Additional space to leave below each text line, in pixels (a positive
+integer). @xref{Line Height}, for more information.
+@end table
+
+@node Buffer Parameters
+@subsubsection Buffer Parameters
+ These frame parameters, meaningful on all kinds of terminals, deal
+with which buffers have been, or should, be displayed in the frame.
+
+@table @code
@item minibuffer
Whether this frame has its own minibuffer. The value @code{t} means
yes, @code{nil} means no, @code{only} means this frame is just a
The buffer-predicate function for this frame. The function
@code{other-buffer} uses this predicate (from the selected frame) to
decide which buffers it should consider, if the predicate is not
-@code{nil}. It calls the predicate with one arg, a buffer, once for
+@code{nil}. It calls the predicate with one argument, a buffer, once for
each buffer; if the predicate returns a non-@code{nil} value, it
considers that buffer.
@item buffer-list
-A list of buffers recently selected in this frame.
+A list of buffers that have been selected in this frame,
+ordered most-recently-selected first.
-@item font
-The name of the font for displaying text in the frame. This is a
-string.
+@item unsplittable
+If non-@code{nil}, this frame's window is never split automatically.
+@end table
+
+@node Management Parameters
+@subsubsection Window Management Parameters
+
+ These frame parameters, meaningful only on window system displays,
+interact with the window manager.
+
+@table @code
+@item visibility
+The state of visibility of the frame. There are three possibilities:
+@code{nil} for invisible, @code{t} for visible, and @code{icon} for
+iconified. @xref{Visibility of Frames}.
@item auto-raise
Whether selecting the frame raises it (non-@code{nil} means yes).
@item auto-lower
Whether deselecting the frame lowers it (non-@code{nil} means yes).
-@item vertical-scroll-bars
-Whether the frame has scroll bars for vertical scrolling, and which side
-of the frame they should be on. The possible values are @code{left},
-@code{right}, and @code{nil} for no scroll bars.
-
-@item horizontal-scroll-bars
-Whether the frame has scroll bars for horizontal scrolling
-(non-@code{nil} means yes). (Horizontal scroll bars are not currently
-implemented.)
-
-@item scroll-bar-width
-The width of the vertical scroll bar, in pixels.
-
@item icon-type
The type of icon to use for this frame when it is iconified. If the
value is a string, that specifies a file containing a bitmap to use.
The name to use in the icon for this frame, when and if the icon
appears. If this is @code{nil}, the frame's title is used.
-@item foreground-color
-The color to use for the image of a character. This is a string; the X
-server defines the meaningful color names.
+@item window-id
+The number of the window-system window used by the frame
+to contain the actual Emacs windows.
-@item background-color
-The color to use for the background of characters.
+@item outer-window-id
+The number of the outermost window-system window used for the whole frame.
-@item mouse-color
-The color for the mouse pointer.
+@item wait-for-wm
+If non-@code{nil}, tell Xt to wait for the window manager to confirm
+geometry changes. Some window managers, including versions of Fvwm2
+and KDE, fail to confirm, so Xt hangs. Set this to @code{nil} to
+prevent hanging with those window managers.
-@item cursor-color
-The color for the cursor that shows point.
+@ignore
+@item parent-id
+@c ??? Not yet working.
+The X window number of the window that should be the parent of this one.
+Specifying this lets you create an Emacs window inside some other
+application's window. (It is not certain this will be implemented; try
+it and see if it works.)
+@end ignore
+@end table
-@item border-color
-The color for the border of the frame.
+@node Cursor Parameters
+@subsubsection Cursor Parameters
+
+ This frame parameter controls the way the cursor looks.
+@table @code
@item cursor-type
-The way to display the cursor. The legitimate values are @code{bar},
-@code{box}, and @code{(bar . @var{width})}. The symbol @code{box}
-specifies an ordinary black box overlaying the character after point;
-that is the default. The symbol @code{bar} specifies a vertical bar
-between characters as the cursor. @code{(bar . @var{width})} specifies
-a bar @var{width} pixels wide.
+How to display the cursor. Legitimate values are:
-@item border-width
-The width in pixels of the window border.
+@table @code
+@item box
+Display a filled box. (This is the default.)
+@item hollow
+Display a hollow box.
+@item nil
+Don't display a cursor.
+@item bar
+Display a vertical bar between characters.
+@item (bar . @var{width})
+Display a vertical bar @var{width} pixels wide between characters.
+@item hbar
+Display a horizontal bar.
+@item (hbar . @var{height})
+Display a horizontal bar @var{height} pixels high.
+@end table
+@end table
-@item internal-border-width
-The distance in pixels between text and border.
+@vindex cursor-type
+The buffer-local variable @code{cursor-type} overrides the value of
+the @code{cursor-type} frame parameter, but if it is @code{t}, that
+means to use the cursor specified for the frame.
+
+@defvar blink-cursor-alist
+This variable specifies how to blink the cursor. Each element has the
+form @code{(@var{on-state} . @var{off-state})}. Whenever the cursor
+type equals @var{on-state} (comparing using @code{equal}), the
+corresponding @var{off-state} specifies what the cursor looks like
+when it blinks ``off.'' Both @var{on-state} and @var{off-state}
+should be suitable values for the @code{cursor-type} frame parameter.
+
+There are various defaults for how to blink each type of cursor, if
+the type is not mentioned as an @var{on-state} here. Changes in this
+variable do not take effect immediately, because the variable is
+examined only when you specify the @code{cursor-type} parameter.
+@end defvar
-@item unsplittable
-If non-@code{nil}, this frame's window is never split automatically.
+@node Color Parameters
+@subsubsection Color Parameters
-@item visibility
-The state of visibility of the frame. There are three possibilities:
-@code{nil} for invisible, @code{t} for visible, and @code{icon} for
-iconified. @xref{Visibility of Frames}.
+ These frame parameters control the use of colors.
-@item menu-bar-lines
-The number of lines to allocate at the top of the frame for a menu bar.
-The default is 1. @xref{Menu Bar}. (In Emacs versions that use the X
-toolkit, there is only one menu bar line; all that matters about the
-number you specify is whether it is greater than zero.)
+@table @code
+@item background-mode
+This parameter is either @code{dark} or @code{light}, according
+to whether the background color is a light one or a dark one.
+
+@item tty-color-mode
+@cindex standard colors for character terminals
+This parameter overrides the terminal's color support as given by the
+system's terminal capabilities database in that this parameter's value
+specifies the color mode to use in terminal frames. The value can be
+either a symbol or a number. A number specifies the number of colors
+to use (and, indirectly, what commands to issue to produce each
+color). For example, @code{(tty-color-mode . 8)} specifies use of the
+ANSI escape sequences for 8 standard text colors. A value of -1 turns
+off color support.
+
+If the parameter's value is a symbol, it specifies a number through
+the value of @code{tty-color-mode-alist}, and the associated number is
+used instead.
+
+@item screen-gamma
+@cindex gamma correction
+If this is a number, Emacs performs ``gamma correction'' which adjusts
+the brightness of all colors. The value should be the screen gamma of
+your display, a floating point number.
+
+Usual PC monitors have a screen gamma of 2.2, so color values in
+Emacs, and in X windows generally, are calibrated to display properly
+on a monitor with that gamma value. If you specify 2.2 for
+@code{screen-gamma}, that means no correction is needed. Other values
+request correction, designed to make the corrected colors appear on
+your screen the way they would have appeared without correction on an
+ordinary monitor with a gamma value of 2.2.
+
+If your monitor displays colors too light, you should specify a
+@code{screen-gamma} value smaller than 2.2. This requests correction
+that makes colors darker. A screen gamma value of 1.5 may give good
+results for LCD color displays.
+@end table
-@item parent-id
-@c ??? Not yet working.
-The X window number of the window that should be the parent of this one.
-Specifying this lets you create an Emacs window inside some other
-application's window. (It is not certain this will be implemented; try
-it and see if it works.)
+These frame parameters are semi-obsolete in that they are automatically
+equivalent to particular face attributes of particular faces.
+
+@table @code
+@item font
+The name of the font for displaying text in the frame. This is a
+string, either a valid font name for your system or the name of an Emacs
+fontset (@pxref{Fontsets}). It is equivalent to the @code{font}
+attribute of the @code{default} face.
+
+@item foreground-color
+The color to use for the image of a character. It is equivalent to
+the @code{:foreground} attribute of the @code{default} face.
+
+@item background-color
+The color to use for the background of characters. It is equivalent to
+the @code{:background} attribute of the @code{default} face.
+
+@item mouse-color
+The color for the mouse pointer. It is equivalent to the @code{:background}
+attribute of the @code{mouse} face.
+
+@item cursor-color
+The color for the cursor that shows point. It is equivalent to the
+@code{:background} attribute of the @code{cursor} face.
+
+@item border-color
+The color for the border of the frame. It is equivalent to the
+@code{:background} attribute of the @code{border} face.
+
+@item scroll-bar-foreground
+If non-@code{nil}, the color for the foreground of scroll bars. It is
+equivalent to the @code{:foreground} attribute of the
+@code{scroll-bar} face.
+
+@item scroll-bar-background
+If non-@code{nil}, the color for the background of scroll bars. It is
+equivalent to the @code{:background} attribute of the
+@code{scroll-bar} face.
@end table
@node Size and Position
@subsection Frame Size And Position
+@cindex size of frame
+@cindex screen size
+@cindex frame size
+@cindex resize frame
You can read or change the size and position of a frame using the
frame parameters @code{left}, @code{top}, @code{height}, and
@code{width}. Whatever geometry parameters you don't specify are chosen
by the window manager in its usual fashion.
- Here are some special features for working with sizes and positions:
+ Here are some special features for working with sizes and positions.
+(For the precise meaning of ``selected frame'' used by these functions,
+see @ref{Input Focus}.)
@defun set-frame-position frame left top
This function sets the position of the top left corner of @var{frame} to
@var{left} and @var{top}. These arguments are measured in pixels, and
-count from the top left corner of the screen. Negative parameter values
-count up or rightward from the top left corner of the screen.
+normally count from the top left corner of the screen.
+
+Negative parameter values position the bottom edge of the window up from
+the bottom edge of the screen, or the right window edge to the left of
+the right edge of the screen. It would probably be better if the values
+were always counted from the left and top, so that negative arguments
+would position the frame partly off the top or left edge of the screen,
+but it seems inadvisable to change that now.
@end defun
@defun frame-height &optional frame
@defunx frame-width &optional frame
These functions return the height and width of @var{frame}, measured in
-characters. If you don't supply @var{frame}, they use the selected
-frame.
+lines and columns. If you don't supply @var{frame}, they use the
+selected frame.
+@end defun
+
+@defun screen-height
+@defunx screen-width
+These functions are old aliases for @code{frame-height} and
+@code{frame-width}. When you are using a non-window terminal, the size
+of the frame is normally the same as the size of the terminal screen.
@end defun
@defun frame-pixel-height &optional frame
them to units of characters.
@end defun
- The old-fashioned functions @code{set-screen-height} and
-@code{set-screen-width}, which were used to specify the height and width
-of the screen in Emacs versions that did not support multiple frames,
-are still usable. They apply to the selected frame. @xref{Screen
-Size}.
+@defun set-frame-height frame lines &optional pretend
+This function resizes @var{frame} to a height of @var{lines} lines. The
+sizes of existing windows in @var{frame} are altered proportionally to
+fit.
+
+If @var{pretend} is non-@code{nil}, then Emacs displays @var{lines}
+lines of output in @var{frame}, but does not change its value for the
+actual height of the frame. This is only useful for a terminal frame.
+Using a smaller height than the terminal actually implements may be
+useful to reproduce behavior observed on a smaller screen, or if the
+terminal malfunctions when using its whole screen. Setting the frame
+height ``for real'' does not always work, because knowing the correct
+actual size may be necessary for correct cursor positioning on a
+terminal frame.
+@end defun
+
+@defun set-frame-width frame width &optional pretend
+This function sets the width of @var{frame}, measured in characters.
+The argument @var{pretend} has the same meaning as in
+@code{set-frame-height}.
+@end defun
+
+@findex set-screen-height
+@findex set-screen-width
+ The older functions @code{set-screen-height} and
+@code{set-screen-width} were used to specify the height and width of the
+screen, in Emacs versions that did not support multiple frames. They
+are semi-obsolete, but still work; they apply to the selected frame.
+
+@node Geometry
+@subsection Geometry
+
+ Here's how to examine the data in an X-style window geometry
+specification:
@defun x-parse-geometry geom
@cindex geometry specification
-The function @code{x-parse-geometry} converts a standard X windows
+The function @code{x-parse-geometry} converts a standard X window
geometry string to an alist that you can use as part of the argument to
@code{make-frame}.
@example
(x-parse-geometry "35x70+0-0")
- @result{} ((width . 35) (height . 70)
- (left . 0) (top - 0))
+ @result{} ((height . 70) (width . 35)
+ (top - 0) (left . 0))
@end example
@end defun
-@ignore
-New functions @code{set-frame-height} and @code{set-frame-width} set the
-size of a specified frame. The frame is the first argument; the size is
-the second.
-@end ignore
-
@node Frame Titles
@section Frame Titles
-Every frame has a title; most window managers display the frame title at
-the top of the frame. You can specify an explicit title with the
-@code{name} frame property. But normally you don't specify this
-explicitly, and Emacs computes the title automatically.
+ Every frame has a @code{name} parameter; this serves as the default
+for the frame title which window systems typically display at the top of
+the frame. You can specify a name explicitly by setting the @code{name}
+frame property.
-Emacs computes the frame title based on a template stored in the
-variable @code{frame-title-format}.
+ Normally you don't specify the name explicitly, and Emacs computes the
+frame name automatically based on a template stored in the variable
+@code{frame-title-format}. Emacs recomputes the name each time the
+frame is redisplayed.
@defvar frame-title-format
-This variable specifies how to compute a title for a frame
-when you have not explicitly specified one.
-
-The variable's value is actually a mode line construct, just like
-@code{mode-line-format}. @xref{Mode Line Data}.
+This variable specifies how to compute a name for a frame when you have
+not explicitly specified one. The variable's value is actually a mode
+line construct, just like @code{mode-line-format}, except that the
+@samp{%c} and @samp{%l} constructs are ignored. @xref{Mode Line
+Data}.
@end defvar
@defvar icon-title-format
-This variable specifies how to compute the title for an iconified frame,
+This variable specifies how to compute the name for an iconified frame,
when you have not explicitly specified the frame title. This title
appears in the icon itself.
@end defvar
invisible frames). The default value of @code{frame-title-format} uses
@code{multiple-frames} so as to put the buffer name in the frame title
only when there is more than one frame.
+
+The value of this variable is not guaranteed to be accurate except
+while processing @code{frame-title-format} or
+@code{icon-title-format}.
@end defvar
@node Deleting Frames
Frames remain potentially visible until you explicitly @dfn{delete}
them. A deleted frame cannot appear on the screen, but continues to
-exist as a Lisp object until there are no references to it. There is no
-way to cancel the deletion of a frame aside from restoring a saved frame
-configuration (@pxref{Frame Configurations}); this is similar to the
-way windows behave.
+exist as a Lisp object until there are no references to it.
-@deffn Command delete-frame &optional frame
-This function deletes the frame @var{frame}. By default, @var{frame} is
+@deffn Command delete-frame &optional frame force
+@vindex delete-frame-functions
+This function deletes the frame @var{frame}. Unless @var{frame} is a
+tooltip, it first runs the hook @code{delete-frame-functions} (each
+function gets one argument, @var{frame}). By default, @var{frame} is
the selected frame.
+
+A frame cannot be deleted if its minibuffer is used by other frames.
+Normally, you cannot delete a frame if all other frames are invisible,
+but if the @var{force} is non-@code{nil}, then you are allowed to do so.
@end deffn
@defun frame-live-p frame
The function @code{frame-live-p} returns non-@code{nil} if the frame
-@var{frame} has not been deleted.
+@var{frame} has not been deleted. The possible non-@code{nil} return
+values are like those of @code{framep}. @xref{Frames}.
@end defun
Some window managers provide a command to delete a window. These work
@defun frame-list
The function @code{frame-list} returns a list of all the frames that
have not been deleted. It is analogous to @code{buffer-list} for
-buffers. The list that you get is newly created, so modifying the list
-doesn't have any effect on the internals of Emacs.
+buffers, and includes frames on all terminals. The list that you get is
+newly created, so modifying the list doesn't have any effect on the
+internals of Emacs.
@end defun
@defun visible-frame-list
This function returns a list of just the currently visible frames.
@xref{Visibility of Frames}. (Terminal frames always count as
-``visible'', even though only the selected one is actually displayed.)
+``visible,'' even though only the selected one is actually displayed.)
@end defun
@defun next-frame &optional frame minibuf
The function @code{next-frame} lets you cycle conveniently through all
-the frames from an arbitrary starting point. It returns the ``next''
-frame after @var{frame} in the cycle. If @var{frame} is omitted or
-@code{nil}, it defaults to the selected frame.
+the frames on the current display from an arbitrary starting point. It
+returns the ``next'' frame after @var{frame} in the cycle. If
+@var{frame} is omitted or @code{nil}, it defaults to the selected frame
+(@pxref{Input Focus}).
The second argument, @var{minibuf}, says which frames to consider:
the lower right corner (always the minibuffer window, if the frame has
one), and then it moves back to the top. @xref{Cyclic Window Ordering}.
-@defun frame-top-window frame
+@defun frame-first-window &optional frame
This returns the topmost, leftmost window of frame @var{frame}.
+If omitted or @code{nil}, @var{frame} defaults to the selected frame.
@end defun
At any time, exactly one window on any frame is @dfn{selected within the
frame also selects this window. You can get the frame's current
selected window with @code{frame-selected-window}.
-@defun frame-selected-window frame
-This function returns the window on @var{frame} that is selected within
-@var{frame}.
+@defun frame-selected-window &optional frame
+This function returns the window on @var{frame} that is selected
+within @var{frame}. If omitted or @code{nil}, @var{frame} defaults to
+the selected frame.
@end defun
-Conversely, selecting a window for Emacs with @code{select-window} also
+@defun set-frame-selected-window frame window
+This sets the selected window of frame @var{frame} to @var{window}.
+If @var{frame} is @code{nil}, it operates on the selected frame. If
+@var{frame} is the selected frame, this makes @var{window} the
+selected window. This function returns @var{window}.
+@end defun
+
+ Conversely, selecting a window for Emacs with @code{select-window} also
makes that window selected within its frame. @xref{Selecting Windows}.
-Another function that (usually) returns one of the windows in a frame is
-@code{minibuffer-window}. @xref{Minibuffer Misc}.
+ Another function that (usually) returns one of the windows in a given
+frame is @code{minibuffer-window}. @xref{Definition of minibuffer-window}.
@node Minibuffers and Frames
@section Minibuffers and Frames
Normally, each frame has its own minibuffer window at the bottom, which
is used whenever that frame is selected. If the frame has a minibuffer,
-you can get it with @code{minibuffer-window} (@pxref{Minibuffer Misc}).
+you can get it with @code{minibuffer-window} (@pxref{Definition of
+minibuffer-window}).
However, you can also create a frame with no minibuffer. Such a frame
must use the minibuffer window of some other frame. When you create the
@defvar default-minibuffer-frame
This variable specifies the frame to use for the minibuffer window, by
-default. It is always local to the current terminal and cannot be
-buffer-local. @xref{Multiple Displays}.
+default. It does not affect existing frames. It is always local to
+the current terminal and cannot be buffer-local. @xref{Multiple
+Displays}.
@end defvar
@node Input Focus
At any time, one frame in Emacs is the @dfn{selected frame}. The selected
window always resides on the selected frame.
+When Emacs displays its frames on several terminals (@pxref{Multiple
+Displays}), each terminal has its own selected frame. But only one of
+these is ``@emph{the} selected frame'': it's the frame that belongs to
+the terminal from which the most recent input came. That is, when Emacs
+runs a command that came from a certain terminal, the selected frame is
+the one of that terminal. Since Emacs runs only a single command at any
+given time, it needs to consider only one selected frame at a time; this
+frame is what we call @dfn{the selected frame} in this manual. The
+display on which the selected frame is displayed is the @dfn{selected
+frame's display}.
+
@defun selected-frame
This function returns the selected frame.
@end defun
-The X server normally directs keyboard input to the X window that the
-mouse is in. Some window managers use mouse clicks or keyboard events
-to @dfn{shift the focus} to various X windows, overriding the normal
-behavior of the server.
-
-Lisp programs can switch frames ``temporarily'' by calling
-the function @code{select-frame}. This does not override the window
-manager; rather, it escapes from the window manager's control until
-that control is somehow reasserted.
-
-When using a text-only terminal, there is no window manager; therefore,
-@code{switch-frame} is the only way to switch frames, and the effect
-lasts until overridden by a subsequent call to @code{switch-frame}.
-Only the selected terminal frame is actually displayed on the terminal.
-Each terminal screen except for the initial one has a number, and the
-number of the selected frame appears in the mode line after the word
-@samp{Emacs} (@pxref{Mode Line Variables}).
+Some window systems and window managers direct keyboard input to the
+window object that the mouse is in; others require explicit clicks or
+commands to @dfn{shift the focus} to various window objects. Either
+way, Emacs automatically keeps track of which frame has the focus. To
+switch to a different frame from a Lisp function, call
+@code{select-frame-set-input-focus}.
+
+Lisp programs can also switch frames ``temporarily'' by calling the
+function @code{select-frame}. This does not alter the window system's
+concept of focus; rather, it escapes from the window manager's control
+until that control is somehow reasserted.
+
+When using a text-only terminal, only one frame can be displayed at a
+time on the terminal, so after a call to @code{select-frame}, the next
+redisplay actually displays the newly selected frame. This frame
+remains selected until a subsequent call to @code{select-frame} or
+@code{select-frame-set-input-focus}. Each terminal frame has a number
+which appears in the mode line before the buffer name (@pxref{Mode
+Line Variables}).
+
+@defun select-frame-set-input-focus frame
+This function makes @var{frame} the selected frame, raises it (should
+it happen to be obscured by other frames) and tries to give it the X
+server's focus. On a text-only terminal, the next redisplay displays
+the new frame on the entire terminal screen. The return value of this
+function is not significant.
+@end defun
@c ??? This is not yet implemented properly.
@defun select-frame frame
This function selects frame @var{frame}, temporarily disregarding the
focus of the X server if any. The selection of @var{frame} lasts until
the next time the user does something to select a different frame, or
-until the next time this function is called.
+until the next time this function is called. (If you are using a
+window system, the previously selected frame may be restored as the
+selected frame after return to the command loop, because it still may
+have the window system's input focus.) The specified @var{frame}
+becomes the selected frame, as explained above, and the terminal that
+@var{frame} is on becomes the selected terminal. This function
+returns @var{frame}, or @code{nil} if @var{frame} has been deleted.
+
+In general, you should never use @code{select-frame} in a way that could
+switch to a different terminal without switching back when you're done.
@end defun
-Emacs cooperates with the X server and the window managers by arranging
-to select frames according to what the server and window manager ask
-for. It does so by generating a special kind of input event, called a
-@dfn{focus} event. The command loop handles a focus event by calling
+Emacs cooperates with the window system by arranging to select frames as
+the server and window manager request. It does so by generating a
+special kind of input event, called a @dfn{focus} event, when
+appropriate. The command loop handles a focus event by calling
@code{handle-switch-frame}. @xref{Focus Events}.
@deffn Command handle-switch-frame frame
Don't call it for any other reason.
@end deffn
-@defun redirect-frame-focus frame focus-frame
+@defun redirect-frame-focus frame &optional focus-frame
This function redirects focus from @var{frame} to @var{focus-frame}.
This means that @var{focus-frame} will receive subsequent keystrokes and
events intended for @var{frame}. After such an event, the value of
@code{last-event-frame} will be @var{focus-frame}. Also, switch-frame
events specifying @var{frame} will instead select @var{focus-frame}.
-If @var{focus-frame} is @code{nil}, that cancels any existing
+If @var{focus-frame} is omitted or @code{nil}, that cancels any existing
redirection for @var{frame}, which therefore once again receives its own
events.
change it.
@end defun
+@defopt focus-follows-mouse
+This option is how you inform Emacs whether the window manager transfers
+focus when the user moves the mouse. Non-@code{nil} says that it does.
+When this is so, the command @code{other-frame} moves the mouse to a
+position consistent with the new selected frame. (This option has no
+effect on MS-Windows, where the mouse pointer is always automatically
+moved by the OS to the selected frame.)
+@end defopt
+
@node Visibility of Frames
@section Visibility of Frames
@cindex visible frame
@cindex iconified frame
@cindex frame visibility
-An X window frame may be @dfn{visible}, @dfn{invisible}, or
+A window frame may be @dfn{visible}, @dfn{invisible}, or
@dfn{iconified}. If it is visible, you can see its contents. If it is
iconified, the frame's contents do not appear on the screen, but an icon
does. If the frame is invisible, it doesn't show on the screen, not
it makes the selected frame visible.
@end deffn
-@deffn Command make-frame-invisible &optional frame
+@deffn Command make-frame-invisible &optional frame force
This function makes frame @var{frame} invisible. If you omit
@var{frame}, it makes the selected frame invisible.
+
+Unless @var{force} is non-@code{nil}, this function refuses to make
+@var{frame} invisible if all other frames are invisible..
@end deffn
@deffn Command iconify-frame &optional frame
This returns the visibility status of frame @var{frame}. The value is
@code{t} if @var{frame} is visible, @code{nil} if it is invisible, and
@code{icon} if it is iconified.
+
+On a text-only terminal, all frames are considered visible, whether
+they are currently being displayed or not, and this function returns
+@code{t} for all frames.
@end defun
The visibility status of a frame is also available as a frame
-parameter. You can read or change it as such. @xref{X Frame
+parameter. You can read or change it as such. @xref{Management
Parameters}.
The user can iconify and deiconify frames with the window manager.
@node Raising and Lowering
@section Raising and Lowering Frames
- The X Window System uses a desktop metaphor. Part of this metaphor is
+ Most window systems use a desktop metaphor. Part of this metaphor is
the idea that windows are stacked in a notional third dimension
perpendicular to the screen surface, and thus ordered from ``highest''
-to ``lowest''. Where two X windows overlap, the one higher up covers
-the one underneath. Even an X window at the bottom of the stack can be
-seen if no other X window overlaps it.
+to ``lowest.'' Where two windows overlap, the one higher up covers
+the one underneath. Even a window at the bottom of the stack can be
+seen if no other window overlaps it.
@cindex raising a frame
@cindex lowering a frame
- An X window's place in this ordering is not fixed; in fact, users tend
-to change the order frequently. @dfn{Raising} an X window means moving
-it ``up'', to the top of the stack. @dfn{Lowering} an X window means
+ A window's place in this ordering is not fixed; in fact, users tend
+to change the order frequently. @dfn{Raising} a window means moving
+it ``up,'' to the top of the stack. @dfn{Lowering} a window means
moving it to the bottom of the stack. This motion is in the notional
-third dimension only, and does not change the position of the X window
+third dimension only, and does not change the position of the window
on the screen.
-You can raise and lower Emacs's X windows with these functions:
+ You can raise and lower Emacs frame Windows with these functions:
-@deffn Command raise-frame frame
-This function raises frame @var{frame}.
+@deffn Command raise-frame &optional frame
+This function raises frame @var{frame} (default, the selected frame).
+If @var{frame} is invisible or iconified, this makes it visible.
@end deffn
-@deffn Command lower-frame frame
-This function lowers frame @var{frame}.
+@deffn Command lower-frame &optional frame
+This function lowers frame @var{frame} (default, the selected frame).
@end deffn
@defopt minibuffer-auto-raise
You can also enable auto-raise (raising automatically when a frame is
selected) or auto-lower (lowering automatically when it is deselected)
-for any frame using frame parameters. @xref{X Frame Parameters}.
+for any frame using frame parameters. @xref{Management Parameters}.
@node Frame Configurations
@section Frame Configurations
A @dfn{frame configuration} records the current arrangement of frames,
all their properties, and the window configuration of each one.
+(@xref{Window Configurations}.)
@defun current-frame-configuration
This function returns a frame configuration list that describes
the current arrangement of frames and their contents.
@end defun
-@defun set-frame-configuration configuration
+@defun set-frame-configuration configuration &optional nodelete
This function restores the state of frames described in
-@var{configuration}.
+@var{configuration}. However, this function does not restore deleted
+frames.
+
+Ordinarily, this function deletes all existing frames not listed in
+@var{configuration}. But if @var{nodelete} is non-@code{nil}, the
+unwanted frames are iconified instead.
@end defun
@node Mouse Tracking
button.
@defspec track-mouse body@dots{}
-Execute @var{body}, meanwhile generating input events for mouse motion.
-The code in @var{body} can read these events with @code{read-event} or
-@code{read-key-sequence}. @xref{Motion Events}, for the format of mouse
-motion events.
+This special form executes @var{body}, with generation of mouse motion
+events enabled. Typically @var{body} would use @code{read-event} to
+read the motion events and modify the display accordingly. @xref{Motion
+Events}, for the format of mouse motion events.
The value of @code{track-mouse} is that of the last form in @var{body}.
+You should design @var{body} to return when it sees the up-event that
+indicates the release of the button, or whatever kind of event means
+it is time to stop tracking.
@end defspec
The usual purpose of tracking mouse motion is to indicate on the screen
These functions change the screen appearance instantaneously. The
effect is transient, only until the next ordinary Emacs redisplay. That
-is ok for mouse tracking, since it doesn't make sense for mouse tracking
+is OK for mouse tracking, since it doesn't make sense for mouse tracking
to change the text, and the body of @code{track-mouse} normally reads
the events itself and does not do redisplay.
the top left corner of the inside of @var{frame}.
@end defun
+@defvar mouse-position-function
+If non-@code{nil}, the value of this variable is a function for
+@code{mouse-position} to call. @code{mouse-position} calls this
+function just before returning, with its normal return value as the
+sole argument, and it returns whatever this function returns to it.
+
+This abnormal hook exists for the benefit of packages like
+@file{xt-mouse.el} that need to do mouse handling at the Lisp level.
+@end defvar
+
@defun set-mouse-position frame x y
This function @dfn{warps the mouse} to position @var{x}, @var{y} in
frame @var{frame}. The arguments @var{x} and @var{y} are integers,
giving the position in characters relative to the top left corner of the
-inside of @var{frame}.
+inside of @var{frame}. If @var{frame} is not visible, this function
+does nothing. The return value is not significant.
@end defun
@defun mouse-pixel-position
This function warps the mouse like @code{set-mouse-position} except that
@var{x} and @var{y} are in units of pixels rather than units of
characters. These coordinates are not required to be within the frame.
+
+If @var{frame} is not visible, this function does nothing. The return
+value is not significant.
@end defun
@need 3000
@node Pop-Up Menus
@section Pop-Up Menus
- When using X windows, a Lisp program can pop up a menu which the
-user can choose from with the mouse.
+ When using a window system, a Lisp program can pop up a menu so that
+the user can choose an alternative with the mouse.
@defun x-popup-menu position menu
This function displays a pop-up menu and returns an indication of
what selection the user makes.
The argument @var{position} specifies where on the screen to put the
-menu. It can be either a mouse button event (which says to put the menu
-where the user actuated the button) or a list of this form:
+top left corner of the menu. It can be either a mouse button event
+(which says to put the menu where the user actuated the button) or a
+list of this form:
@example
((@var{xoffset} @var{yoffset}) @var{window})
@noindent
where @var{xoffset} and @var{yoffset} are coordinates, measured in
-pixels, counting from the top left corner of @var{window}'s frame.
+pixels, counting from the top left corner of @var{window}. @var{window}
+may be a window or a frame.
If @var{position} is @code{t}, it means to use the current mouse
position. If @var{position} is @code{nil}, it means to precompute the
without actually displaying or popping up the menu.
The argument @var{menu} says what to display in the menu. It can be a
-keymap or a list of keymaps (@pxref{Menu Keymaps}). Alternatively, it
-can have the following form:
+keymap or a list of keymaps (@pxref{Menu Keymaps}). In this case, the
+return value is the list of events corresponding to the user's choice.
+(This list has more than one element if the choice occurred in a
+submenu.) Note that @code{x-popup-menu} does not actually execute the
+command bound to that sequence of events.
+
+Alternatively, @var{menu} can have the following form:
@example
(@var{title} @var{pane1} @var{pane2}...)
where each pane is a list of form
@example
-(@var{title} (@var{line} . @var{item})...)
+(@var{title} @var{item1} @var{item2}...)
@end example
-Each @var{line} should be a string, and each @var{item} should be the
-value to return if that @var{line} is chosen.
+Each item should normally be a cons cell @code{(@var{line} . @var{value})},
+where @var{line} is a string, and @var{value} is the value to return if
+that @var{line} is chosen. An item can also be a string; this makes a
+non-selectable line in the menu.
+
+If the user gets rid of the menu without making a valid choice, for
+instance by clicking the mouse away from a valid choice or by typing
+keyboard input, then this normally results in a quit and
+@code{x-popup-menu} does not return. But if @var{position} is a mouse
+button event (indicating that the user invoked the menu with the
+mouse) then no quit occurs and @code{x-popup-menu} returns @code{nil}.
@end defun
@strong{Usage note:} Don't use @code{x-popup-menu} to display a menu
submenu using @code{x-popup-menu}, it cannot work with the menu bar in
an integrated fashion. This is why all menu bar submenus are
implemented with menu keymaps within the parent menu, and never with
-@code{x-popup-menu}. @xref{Menu Bar},
+@code{x-popup-menu}. @xref{Menu Bar}.
If you want a menu bar submenu to have contents that vary, you should
still use a menu keymap to implement it. To make the contents vary, add
@section Dialog Boxes
@cindex dialog boxes
- A dialog box is a variant of a pop-up menu. It looks a little
-different (if Emacs uses an X toolkit), it always appears in the center
-of a frame, and it has just one level and one pane. The main use of
-dialog boxes is for asking questions that the user can answer with
-``yes'', ``no'', and a few other alternatives. The functions
+ A dialog box is a variant of a pop-up menu---it looks a little
+different, it always appears in the center of a frame, and it has just
+one level and one or more buttons. The main use of dialog boxes is
+for asking questions that the user can answer with ``yes,'' ``no,''
+and a few other alternatives. With a single button, they can also
+force the user to acknowledge important information. The functions
@code{y-or-n-p} and @code{yes-or-no-p} use dialog boxes instead of the
keyboard, when called from commands invoked by mouse clicks.
-@defun x-popup-dialog position contents
+@defun x-popup-dialog position contents &optional header
This function displays a pop-up dialog box and returns an indication of
what selection the user makes. The argument @var{contents} specifies
the alternatives to offer; it has this format:
The return value is @var{value} from the chosen alternative.
-An element of the list may be just a string instead of a cons cell
-@code{(@var{string} . @var{value})}. That makes a box that cannot
-be selected.
+As for @code{x-popup-menu}, an element of the list may be just a
+string instead of a cons cell @code{(@var{string} . @var{value})}.
+That makes a box that cannot be selected.
If @code{nil} appears in the list, it separates the left-hand items from
the right-hand items; items that precede the @code{nil} appear on the
Dialog boxes always appear in the center of a frame; the argument
@var{position} specifies which frame. The possible values are as in
-@code{x-popup-menu}, but the precise coordinates don't matter; only the
-frame matters.
+@code{x-popup-menu}, but the precise coordinates or the individual
+window don't matter; only the frame matters.
-If your Emacs executable does not use an X toolkit, then it cannot
-display a real dialog box; so instead it displays the same items in a
-pop-up menu in the center of the frame.
+If @var{header} is non-@code{nil}, the frame title for the box is
+@samp{Information}, otherwise it is @samp{Question}. The former is used
+for @code{message-box} (@pxref{message-box}).
+
+In some configurations, Emacs cannot display a real dialog box; so
+instead it displays the same items in a pop-up menu in the center of the
+frame.
+
+If the user gets rid of the dialog box without making a valid choice,
+for instance using the window manager, then this produces a quit and
+@code{x-popup-dialog} does not return.
@end defun
-@node Pointer Shapes
-@section Pointer Shapes
+@node Pointer Shape
+@section Pointer Shape
@cindex pointer shape
@cindex mouse pointer shape
- These variables specify which shape to use for the mouse pointer in
-various situations:
+ You can specify the mouse pointer style for particular text or
+images using the @code{pointer} text property, and for images with the
+@code{:pointer} and @code{:map} image properties. The values you can
+use in these properties are @code{text} (or @code{nil}), @code{arrow},
+@code{hand}, @code{vdrag}, @code{hdrag}, @code{modeline}, and
+@code{hourglass}. @code{text} stands for the usual mouse pointer
+style used over text.
+
+ Over void parts of the window (parts that do not correspond to any
+of the buffer contents), the mouse pointer usually uses the
+@code{arrow} style, but you can specify a different style (one of
+those above) by setting @code{void-text-area-pointer}.
+
+@defvar void-text-area-pointer
+This variable specifies the mouse pointer style for void text areas.
+These include the areas after the end of a line or below the last line
+in the buffer. The default is to use the @code{arrow} (non-text)
+pointer style.
+@end defvar
-@table @code
-@item x-pointer-shape
-@vindex x-pointer-shape
-This variable specifies the pointer shape to use ordinarily in the Emacs
-frame.
+ You can specify what the @code{text} pointer style really looks like
+by setting the variable @code{x-pointer-shape}.
-@item x-sensitive-text-pointer-shape
-@vindex x-sensitive-text-pointer-shape
+@defvar x-pointer-shape
+This variable specifies the pointer shape to use ordinarily in the
+Emacs frame, for the @code{text} pointer style.
+@end defvar
+
+@defvar x-sensitive-text-pointer-shape
This variable specifies the pointer shape to use when the mouse
is over mouse-sensitive text.
-@end table
+@end defvar
These variables affect newly created frames. They do not normally
-affect existing frames; however, if you set the mouse color of a frame,
-that also updates its pointer shapes based on the current values of
-these variables. @xref{X Frame Parameters}.
+affect existing frames; however, if you set the mouse color of a
+frame, that also installs the current value of those two variables.
+@xref{Color Parameters}.
The values you can use, to specify either of these pointer shapes, are
defined in the file @file{lisp/term/x-win.el}. Use @kbd{M-x apropos
@key{RET} x-pointer @key{RET}} to see a list of them.
-@node X Selections
-@section X Selections
-@cindex selection (for X windows)
+@node Window System Selections
+@section Window System Selections
+@cindex selection (for window systems)
The X server records a set of @dfn{selections} which permit transfer of
data between application programs. The various selections are
symbols. X clients including Emacs can read or set the selection for
any given type.
-@defun x-set-selection type data
+@deffn Command x-set-selection type data
This function sets a ``selection'' in the X server. It takes two
arguments: a selection type @var{type}, and the value to assign to it,
@var{data}. If @var{data} is @code{nil}, it means to clear out the
selection values.
Each possible @var{type} has its own selection value, which changes
-independently. The usual values of @var{type} are @code{PRIMARY} and
-@code{SECONDARY}; these are symbols with upper-case names, in accord
-with X Window System conventions. The default is @code{PRIMARY}.
-@end defun
+independently. The usual values of @var{type} are @code{PRIMARY},
+@code{SECONDARY} and @code{CLIPBOARD}; these are symbols with upper-case
+names, in accord with X Window System conventions. If @var{type} is
+@code{nil}, that stands for @code{PRIMARY}.
+
+This function returns @var{data}.
+@end deffn
@defun x-get-selection &optional type data-type
This function accesses selections set up by Emacs or by other X
The @var{data-type} argument specifies the form of data conversion to
use, to convert the raw data obtained from another X client into Lisp
data. Meaningful values include @code{TEXT}, @code{STRING},
-@code{TARGETS}, @code{LENGTH}, @code{DELETE}, @code{FILE_NAME},
-@code{CHARACTER_POSITION}, @code{LINE_NUMBER}, @code{COLUMN_NUMBER},
-@code{OWNER_OS}, @code{HOST_NAME}, @code{USER}, @code{CLASS},
-@code{NAME}, @code{ATOM}, and @code{INTEGER}. (These are symbols with
-upper-case names in accord with X conventions.) The default for
-@var{data-type} is @code{STRING}.
+@code{UTF8_STRING}, @code{TARGETS}, @code{LENGTH}, @code{DELETE},
+@code{FILE_NAME}, @code{CHARACTER_POSITION}, @code{NAME},
+@code{LINE_NUMBER}, @code{COLUMN_NUMBER}, @code{OWNER_OS},
+@code{HOST_NAME}, @code{USER}, @code{CLASS}, @code{ATOM}, and
+@code{INTEGER}. (These are symbols with upper-case names in accord
+with X conventions.) The default for @var{data-type} is
+@code{STRING}.
@end defun
@cindex cut buffer
-The X server also has a set of numbered @dfn{cut buffers} which can
+The X server also has a set of eight numbered @dfn{cut buffers} which can
store text or other data being moved between applications. Cut buffers
are considered obsolete, but Emacs supports them for the sake of X
-clients that still use them.
+clients that still use them. Cut buffers are numbered from 0 to 7.
-@defun x-get-cut-buffer n
+@defun x-get-cut-buffer &optional n
This function returns the contents of cut buffer number @var{n}.
+If omitted @var{n} defaults to 0.
@end defun
-@defun x-set-cut-buffer string
+@defun x-set-cut-buffer string &optional push
+@anchor{Definition of x-set-cut-buffer}
This function stores @var{string} into the first cut buffer (cut buffer
-0), moving the other values down through the series of cut buffers, much
-like the way successive kills in Emacs move down the kill ring.
+0). If @var{push} is @code{nil}, only the first cut buffer is changed.
+If @var{push} is non-@code{nil}, that says to move the values down
+through the series of cut buffers, much like the way successive kills in
+Emacs move down the kill ring. In other words, the previous value of
+the first cut buffer moves into the second cut buffer, and the second to
+the third, and so on through all eight cut buffers.
@end defun
-@node Font Names
-@section Looking up Font Names
+@defvar selection-coding-system
+This variable specifies the coding system to use when reading and
+writing selections or the clipboard. @xref{Coding
+Systems}. The default is @code{compound-text-with-extensions}, which
+converts to the text representation that X11 normally uses.
+@end defvar
-@defun x-list-font pattern &optional face frame maximum
-This function returns a list of available font names that match
-@var{pattern}. If the optional arguments FACE and FRAME are specified,
-then the list is limited to fonts that are the same size as @var{face}
-currently is on @var{frame}.
+@cindex clipboard support (for MS-Windows)
+When Emacs runs on MS-Windows, it does not implement X selections in
+general, but it does support the clipboard. @code{x-get-selection}
+and @code{x-set-selection} on MS-Windows support the text data type
+only; if the clipboard holds other types of data, Emacs treats the
+clipboard as empty.
+
+@cindex scrap support (for Mac OS)
+On Mac OS, selection-like data transfer between applications is
+performed through a mechanism called @dfn{scraps}. The clipboard is a
+particular scrap named @code{com.apple.scrap.clipboard}. Types of scrap
+data are called @dfn{scrap flavor types}, which are identified by
+four-char codes such as @code{TEXT}. Emacs associates a selection with
+a scrap, and a selection type with a scrap flavor type via
+@code{mac-scrap-name} and @code{mac-ostype} properties, respectively.
-The argument @var{pattern} should be a string, perhaps with wildcard
-characters: the @samp{*} character matches any substring, and the
-@samp{?} character matches any single character. Pattern matching
-of font names ignores case.
+@example
+(get 'CLIPBOARD 'mac-scrap-name)
+ @result{} "com.apple.scrap.clipboard"
+(get 'com.apple.traditional-mac-plain-text 'mac-ostype)
+ @result{} "TEXT"
+@end example
-If you specify @var{face} and @var{frame}, @var{face} should be a face name
-(a symbol) and @var{frame} should be a frame.
+Conventionally, selection types for scrap flavor types on Mac OS have
+the form of @acronym{UTI, Uniform Type Identifier} such as
+@code{com.apple.traditional-mac-plain-text},
+@code{public.utf16-plain-text}, and @code{public.file-url}.
+
+@defopt x-select-enable-clipboard
+If this is non-@code{nil}, the Emacs yank functions consult the
+clipboard before the primary selection, and the kill functions store in
+the clipboard as well as the primary selection. Otherwise they do not
+access the clipboard at all. The default is @code{nil} on most systems,
+but @code{t} on MS-Windows and Mac.
+@end defopt
-The optional argument @var{maximum} sets a limit on how many fonts to
-return. If this is non-@code{nil}, then the return value is truncated
-after the first @var{maximum} matching fonts. Specifying a small value
-for @var{maximum} can make this function much faster, in cases where
-many fonts match the pattern.
-@end defun
+@node Drag and Drop
+@section Drag and Drop
+
+@vindex x-dnd-test-function
+@vindex x-dnd-known-types
+ When a user drags something from another application over Emacs, that other
+application expects Emacs to tell it if Emacs can handle the data that is
+dragged. The variable @code{x-dnd-test-function} is used by Emacs to determine
+what to reply. The default value is @code{x-dnd-default-test-function}
+which accepts drops if the type of the data to be dropped is present in
+@code{x-dnd-known-types}. You can customize @code{x-dnd-test-function} and/or
+@code{x-dnd-known-types} if you want Emacs to accept or reject drops based
+on some other criteria.
+
+@vindex x-dnd-types-alist
+ If you want to change the way Emacs handles drop of different types
+or add a new type, customize @code{x-dnd-types-alist}. This requires
+detailed knowledge of what types other applications use for drag and
+drop.
+
+@vindex dnd-protocol-alist
+ When an URL is dropped on Emacs it may be a file, but it may also be
+another URL type (ftp, http, etc.). Emacs first checks
+@code{dnd-protocol-alist} to determine what to do with the URL. If
+there is no match there and if @code{browse-url-browser-function} is
+an alist, Emacs looks for a match there. If no match is found the
+text for the URL is inserted. If you want to alter Emacs behavior,
+you can customize these variables.
@node Color Names
@section Color Names
-@defun x-color-defined-p color &optional frame
+@cindex color names
+@cindex specify color
+@cindex numerical RGB color specification
+ A color name is text (usually in a string) that specifies a color.
+Symbolic names such as @samp{black}, @samp{white}, @samp{red}, etc.,
+are allowed; use @kbd{M-x list-colors-display} to see a list of
+defined names. You can also specify colors numerically in forms such
+as @samp{#@var{rgb}} and @samp{RGB:@var{r}/@var{g}/@var{b}}, where
+@var{r} specifies the red level, @var{g} specifies the green level,
+and @var{b} specifies the blue level. You can use either one, two,
+three, or four hex digits for @var{r}; then you must use the same
+number of hex digits for all @var{g} and @var{b} as well, making
+either 3, 6, 9 or 12 hex digits in all. (See the documentation of the
+X Window System for more details about numerical RGB specification of
+colors.)
+
+ These functions provide a way to determine which color names are
+valid, and what they look like. In some cases, the value depends on the
+@dfn{selected frame}, as described below; see @ref{Input Focus}, for the
+meaning of the term ``selected frame.''
+
+@defun color-defined-p color &optional frame
This function reports whether a color name is meaningful. It returns
@code{t} if so; otherwise, @code{nil}. The argument @var{frame} says
which frame's display to ask about; if @var{frame} is omitted or
@code{nil}, the selected frame is used.
Note that this does not tell you whether the display you are using
-really supports that color. You can ask for any defined color on any
-kind of display, and you will get some result---that is how the X server
-works. Here's an approximate way to test whether your display supports
-the color @var{color}:
+really supports that color. When using X, you can ask for any defined
+color on any kind of display, and you will get some result---typically,
+the closest it can do. To determine whether a frame can really display
+a certain color, use @code{color-supported-p} (see below).
+
+@findex x-color-defined-p
+This function used to be called @code{x-color-defined-p},
+and that name is still supported as an alias.
+@end defun
-@example
-(defun x-color-supported-p (color &optional frame)
- (and (x-color-defined-p color frame)
- (or (x-display-color-p frame)
- (member color '("black" "white"))
- (and (> (x-display-planes frame) 1)
- (equal color "gray")))))
-@end example
+@defun defined-colors &optional frame
+This function returns a list of the color names that are defined
+and supported on frame @var{frame} (default, the selected frame).
+If @var{frame} does not support colors, the value is @code{nil}.
+
+@findex x-defined-colors
+This function used to be called @code{x-defined-colors},
+and that name is still supported as an alias.
+@end defun
+
+@defun color-supported-p color &optional frame background-p
+This returns @code{t} if @var{frame} can really display the color
+@var{color} (or at least something close to it). If @var{frame} is
+omitted or @code{nil}, the question applies to the selected frame.
+
+Some terminals support a different set of colors for foreground and
+background. If @var{background-p} is non-@code{nil}, that means you are
+asking whether @var{color} can be used as a background; otherwise you
+are asking whether it can be used as a foreground.
+
+The argument @var{color} must be a valid color name.
+@end defun
+
+@defun color-gray-p color &optional frame
+This returns @code{t} if @var{color} is a shade of gray, as defined on
+@var{frame}'s display. If @var{frame} is omitted or @code{nil}, the
+question applies to the selected frame. If @var{color} is not a valid
+color name, this function returns @code{nil}.
@end defun
-@defun x-color-values color &optional frame
+@defun color-values color &optional frame
+@cindex rgb value
This function returns a value that describes what @var{color} should
-ideally look like. If @var{color} is defined, the value is a list of
-three integers, which give the amount of red, the amount of green, and
-the amount of blue. Each integer ranges in principle from 0 to 65535,
-but in practice no value seems to be above 65280. If @var{color} is not
-defined, the value is @code{nil}.
+ideally look like on @var{frame}. If @var{color} is defined, the
+value is a list of three integers, which give the amount of red, the
+amount of green, and the amount of blue. Each integer ranges in
+principle from 0 to 65535, but some displays may not use the full
+range. This three-element list is called the @dfn{rgb values} of the
+color.
+
+If @var{color} is not defined, the value is @code{nil}.
@example
-(x-color-values "black")
+(color-values "black")
@result{} (0 0 0)
-(x-color-values "white")
+(color-values "white")
@result{} (65280 65280 65280)
-(x-color-values "red")
+(color-values "red")
@result{} (65280 0 0)
-(x-color-values "pink")
+(color-values "pink")
@result{} (65280 49152 51968)
-(x-color-values "hungry")
+(color-values "hungry")
@result{} nil
@end example
-The color values are returned for @var{frame}'s display. If @var{frame}
-is omitted or @code{nil}, the information is return for the selected
-frame's display.
+The color values are returned for @var{frame}'s display. If
+@var{frame} is omitted or @code{nil}, the information is returned for
+the selected frame's display. If the frame cannot display colors, the
+value is @code{nil}.
+
+@findex x-color-values
+This function used to be called @code{x-color-values},
+and that name is still supported as an alias.
+@end defun
+
+@node Text Terminal Colors
+@section Text Terminal Colors
+@cindex colors on text-only terminals
+
+ Text-only terminals usually support only a small number of colors,
+and the computer uses small integers to select colors on the terminal.
+This means that the computer cannot reliably tell what the selected
+color looks like; instead, you have to inform your application which
+small integers correspond to which colors. However, Emacs does know
+the standard set of colors and will try to use them automatically.
+
+ The functions described in this section control how terminal colors
+are used by Emacs.
+
+ Several of these functions use or return @dfn{rgb values}, described
+in @ref{Color Names}.
+
+ These functions accept a display (either a frame or the name of a
+terminal) as an optional argument. We hope in the future to make Emacs
+support more than one text-only terminal at one time; then this argument
+will specify which terminal to operate on (the default being the
+selected frame's terminal; @pxref{Input Focus}). At present, though,
+the @var{frame} argument has no effect.
+
+@defun tty-color-define name number &optional rgb frame
+This function associates the color name @var{name} with
+color number @var{number} on the terminal.
+
+The optional argument @var{rgb}, if specified, is an rgb value, a list
+of three numbers that specify what the color actually looks like.
+If you do not specify @var{rgb}, then this color cannot be used by
+@code{tty-color-approximate} to approximate other colors, because
+Emacs will not know what it looks like.
+@end defun
+
+@defun tty-color-clear &optional frame
+This function clears the table of defined colors for a text-only terminal.
+@end defun
+
+@defun tty-color-alist &optional frame
+This function returns an alist recording the known colors supported by a
+text-only terminal.
+
+Each element has the form @code{(@var{name} @var{number} . @var{rgb})}
+or @code{(@var{name} @var{number})}. Here, @var{name} is the color
+name, @var{number} is the number used to specify it to the terminal.
+If present, @var{rgb} is a list of three color values (for red, green,
+and blue) that says what the color actually looks like.
+@end defun
+
+@defun tty-color-approximate rgb &optional frame
+This function finds the closest color, among the known colors
+supported for @var{display}, to that described by the rgb value
+@var{rgb} (a list of color values). The return value is an element of
+@code{tty-color-alist}.
+@end defun
+
+@defun tty-color-translate color &optional frame
+This function finds the closest color to @var{color} among the known
+colors supported for @var{display} and returns its index (an integer).
+If the name @var{color} is not defined, the value is @code{nil}.
@end defun
@node Resources
@defun x-get-resource attribute class &optional component subclass
The function @code{x-get-resource} retrieves a resource value from the X
-Windows defaults database.
+Window defaults database.
Resources are indexed by a combination of a @dfn{key} and a @dfn{class}.
This function searches using a key of the form
variable to some other string, around a call to @code{x-get-resource}.
@end defvar
- @xref{Resources X,, X Resources, emacs, The GNU Emacs Manual}.
+@defvar x-resource-name
+This variable specifies the instance name that @code{x-get-resource}
+should look up. The default value is the name Emacs was invoked with,
+or the value specified with the @samp{-name} or @samp{-rn} switches.
+@end defvar
+
+To illustrate some of the above, suppose that you have the line:
+
+@example
+xterm.vt100.background: yellow
+@end example
-@node Server Data
-@section Data about the X Server
+@noindent
+in your X resources file (whose name is usually @file{~/.Xdefaults}
+or @file{~/.Xresources}). Then:
- This section describes functions you can use to get information about
-the capabilities and origin of an X display that Emacs is using. Each
-of these functions lets you specify the display you are interested in:
-the @var{display} argument can be either a display name, or a frame
-(meaning use the display that frame is on). If you omit the
-@var{display} argument, or specify @code{nil}, that means to use the
-selected frame's display.
+@example
+@group
+(let ((x-resource-class "XTerm") (x-resource-name "xterm"))
+ (x-get-resource "vt100.background" "VT100.Background"))
+ @result{} "yellow"
+@end group
+@group
+(let ((x-resource-class "XTerm") (x-resource-name "xterm"))
+ (x-get-resource "background" "VT100" "vt100" "Background"))
+ @result{} "yellow"
+@end group
+@end example
-@defun x-display-screens &optional display
-This function returns the number of screens associated with the display.
+ @xref{X Resources,, X Resources, emacs, The GNU Emacs Manual}.
+
+@node Display Feature Testing
+@section Display Feature Testing
+@cindex display feature testing
+
+ The functions in this section describe the basic capabilities of a
+particular display. Lisp programs can use them to adapt their behavior
+to what the display can do. For example, a program that ordinarily uses
+a popup menu could use the minibuffer if popup menus are not supported.
+
+ The optional argument @var{display} in these functions specifies which
+display to ask the question about. It can be a display name, a frame
+(which designates the display that frame is on), or @code{nil} (which
+refers to the selected frame's display, @pxref{Input Focus}).
+
+ @xref{Color Names}, @ref{Text Terminal Colors}, for other functions to
+obtain information about displays.
+
+@defun display-popup-menus-p &optional display
+This function returns @code{t} if popup menus are supported on
+@var{display}, @code{nil} if not. Support for popup menus requires that
+the mouse be available, since the user cannot choose menu items without
+a mouse.
@end defun
-@defun x-server-version &optional display
-This function returns the list of version numbers of the X server
-running the display.
+@defun display-graphic-p &optional display
+@cindex frames, more than one on display
+@cindex fonts, more than one on display
+This function returns @code{t} if @var{display} is a graphic display
+capable of displaying several frames and several different fonts at
+once. This is true for displays that use a window system such as X, and
+false for text-only terminals.
@end defun
-@defun x-server-vendor &optional display
-This function returns the vendor that provided the X server software.
+@defun display-mouse-p &optional display
+@cindex mouse, availability
+This function returns @code{t} if @var{display} has a mouse available,
+@code{nil} if not.
@end defun
-@defun x-display-pixel-height &optional display
-This function returns the height of the screen in pixels.
+@defun display-color-p &optional display
+@findex x-display-color-p
+This function returns @code{t} if the screen is a color screen.
+It used to be called @code{x-display-color-p}, and that name
+is still supported as an alias.
+@end defun
+
+@defun display-grayscale-p &optional display
+This function returns @code{t} if the screen can display shades of gray.
+(All color displays can do this.)
+@end defun
+
+@defun display-supports-face-attributes-p attributes &optional display
+@anchor{Display Face Attribute Testing}
+This function returns non-@code{nil} if all the face attributes in
+@var{attributes} are supported (@pxref{Face Attributes}).
+
+The definition of `supported' is somewhat heuristic, but basically
+means that a face containing all the attributes in @var{attributes},
+when merged with the default face for display, can be represented in a
+way that's
+
+@enumerate
+@item
+different in appearance than the default face, and
+
+@item
+`close in spirit' to what the attributes specify, if not exact.
+@end enumerate
+
+Point (2) implies that a @code{:weight black} attribute will be
+satisfied by any display that can display bold, as will
+@code{:foreground "yellow"} as long as some yellowish color can be
+displayed, but @code{:slant italic} will @emph{not} be satisfied by
+the tty display code's automatic substitution of a `dim' face for
+italic.
@end defun
-@defun x-display-mm-height &optional display
-This function returns the height of the screen in millimeters.
+@defun display-selections-p &optional display
+This function returns @code{t} if @var{display} supports selections.
+Windowed displays normally support selections, but they may also be
+supported in some other cases.
+@end defun
+
+@defun display-images-p &optional display
+This function returns @code{t} if @var{display} can display images.
+Windowed displays ought in principle to handle images, but some
+systems lack the support for that. On a display that does not support
+images, Emacs cannot display a tool bar.
+@end defun
+
+@defun display-screens &optional display
+This function returns the number of screens associated with the display.
+@end defun
+
+@defun display-pixel-height &optional display
+This function returns the height of the screen in pixels.
+On a character terminal, it gives the height in characters.
@end defun
-@defun x-display-pixel-width &optional display
+@defun display-pixel-width &optional display
This function returns the width of the screen in pixels.
+On a character terminal, it gives the width in characters.
@end defun
-@defun x-display-mm-width &optional display
-This function returns the width of the screen in millimeters.
+@defun display-mm-height &optional display
+This function returns the height of the screen in millimeters,
+or @code{nil} if Emacs cannot get that information.
@end defun
-@defun x-display-backing-store &optional display
-This function returns the backing store capability of the screen.
+@defun display-mm-width &optional display
+This function returns the width of the screen in millimeters,
+or @code{nil} if Emacs cannot get that information.
+@end defun
+
+@defvar display-mm-dimensions-alist
+This variable allows the user to specify the dimensions of graphical
+displays returned by @code{display-mm-height} and
+@code{display-mm-width} in case the system provides incorrect values.
+@end defvar
+
+@defun display-backing-store &optional display
+This function returns the backing store capability of the display.
+Backing store means recording the pixels of windows (and parts of
+windows) that are not exposed, so that when exposed they can be
+displayed very quickly.
+
Values can be the symbols @code{always}, @code{when-mapped}, or
-@code{not-useful}.
+@code{not-useful}. The function can also return @code{nil}
+when the question is inapplicable to a certain kind of display.
@end defun
-@defun x-display-save-under &optional display
+@defun display-save-under &optional display
This function returns non-@code{nil} if the display supports the
-SaveUnder feature.
+SaveUnder feature. That feature is used by pop-up windows
+to save the pixels they obscure, so that they can pop down
+quickly.
@end defun
-@defun x-display-planes &optional display
+@defun display-planes &optional display
This function returns the number of planes the display supports.
+This is typically the number of bits per pixel.
+For a tty display, it is log to base two of the number of colors supported.
@end defun
-@defun x-display-visual-class &optional display
+@defun display-visual-class &optional display
This function returns the visual class for the screen. The value is one
of the symbols @code{static-gray}, @code{gray-scale},
@code{static-color}, @code{pseudo-color}, @code{true-color}, and
@code{direct-color}.
@end defun
-@defun x-display-grayscale-p &optional display
-This function returns @code{t} if the screen can display shades of gray.
+@defun display-color-cells &optional display
+This function returns the number of color cells the screen supports.
@end defun
-@defun x-display-color-p &optional display
-This function returns @code{t} if the screen is a color screen.
+ These functions obtain additional information specifically
+about X displays.
+
+@defun x-server-version &optional display
+This function returns the list of version numbers of the X server
+running the display. The value is a list of three integers: the major
+and minor version numbers of the X protocol, and the
+distributor-specific release number of the X server software itself.
@end defun
-@defun x-display-color-cells &optional display
-This function returns the number of color cells the screen supports.
+@defun x-server-vendor &optional display
+This function returns the ``vendor'' that provided the X server
+software (as a string). Really this means whoever distributes the X
+server.
+
+When the developers of X labelled software distributors as
+``vendors,'' they showed their false assumption that no system could
+ever be developed and distributed noncommercially.
@end defun
@ignore
@defvar x-no-window-manager
-This variable's value is is @code{t} if no X window manager is in use.
+This variable's value is @code{t} if no X window manager is in use.
@end defvar
@end ignore
The functions @code{x-pixel-width} and @code{x-pixel-height} return the
width and height of an X Window frame, measured in pixels.
@end ignore
+
+@ignore
+ arch-tag: 94977df6-3dca-4730-b57b-c6329e9282ba
+@end ignore