This section describes functions for resizing a window without changing the size of its frame. Because live windows do not overlap, these functions are meaningful only on frames that contain two or more windows: resizing a window also changes the size of at least one other window. If there is just one window on a frame, its size cannot be changed except by resizing the frame (see Frame Size).
Except where noted, these functions also accept internal windows as arguments. Resizing an internal window causes its child windows to be resized to fit the same space.
This function returns delta if the size of window can be
changed vertically by delta lines. If the optional argument
horizontal is non-nil, it instead returns delta if
window can be resized horizontally by delta columns. It
does not actually change the window size.
If window is nil, it defaults to the selected window.
A positive value of delta means to check whether the window can be enlarged by that number of lines or columns; a negative value of delta means to check whether the window can be shrunk by that many lines or columns. If delta is non-zero, a return value of 0 means that the window cannot be resized.
Normally, the variables window-min-height and
window-min-width specify the smallest allowable window size
(see Window Sizes). However, if the optional argument ignore
is non-nil, this function ignores window-min-height and
window-min-width, as well as window-size-fixed. Instead,
it considers the minimum height of a window as the sum of its top and
bottom decorations plus the text of one line; and its minimum width
as the sum of its left and right decorations plus text that takes two
columns.
If the optional argument pixelwise is non-nil,
delta is interpreted as pixels.
This function resizes window by delta increments. If
horizontal is nil, it changes the height by delta
lines; otherwise, it changes the width by delta columns. A
positive delta means to enlarge the window, and a negative
delta means to shrink it.
If window is nil, it defaults to the selected window. If
the window cannot be resized as demanded, an error is signaled.
The optional argument ignore has the same meaning as for the
function window-resizable above.
If the optional argument pixelwise is non-nil,
delta will be interpreted as pixels.
The choice of which window edges this function alters depends on the
values of the option window-combination-resize and the
combination limits of the involved windows; in some cases, it may alter
both edges. See Recombining Windows. To resize by moving only the
bottom or right edge of a window, use the function
adjust-window-trailing-edge.
This function moves window’s bottom edge by delta lines.
If optional argument horizontal is non-nil, it instead
moves the right edge by delta columns. If window is
nil, it defaults to the selected window.
If the optional argument pixelwise is non-nil,
delta is interpreted as pixels.
A positive delta moves the edge downwards or to the right; a negative delta moves it upwards or to the left. If the edge cannot be moved as far as specified by delta, this function moves it as far as possible but does not signal an error.
This function tries to resize windows adjacent to the edge that is moved. If this is not possible for some reason (e.g., if that adjacent window is fixed-size), it may resize other windows.
If the value of this option is non-nil, Emacs resizes windows in
units of pixels. This currently affects functions like
split-window (see Splitting Windows), maximize-window,
minimize-window, fit-window-to-buffer,
fit-frame-to-buffer and
shrink-window-if-larger-than-buffer (all listed below).
Note that when a frame’s pixel size is not a multiple of its character
size, at least one window may get resized pixelwise even if this
option is nil. The default value is nil.
The following commands resize windows in more specific ways. When called interactively, they act on the selected window.
This command adjusts the height or width of window to fit the text
in it. It returns non-nil if it was able to resize window,
and nil otherwise. If window is omitted or nil, it
defaults to the selected window. Otherwise, it should be a live window.
If window is part of a vertical combination, this function adjusts
window’s height. The new height is calculated from the actual
height of the accessible portion of its buffer. The optional argument
max-height, if non-nil, specifies the maximum total height
that this function can give window. The optional argument
min-height, if non-nil, specifies the minimum total height
that it can give, which overrides the variable window-min-height.
Both max-height and min-height are specified in lines and
include any top or bottom decorations of window.
If window is part of a horizontal combination and the value of the
option fit-window-to-buffer-horizontally (see below) is
non-nil, this function adjusts window’s width. The new
width of window is calculated from the maximum length of its
buffer’s lines that follow the current start position of window.
The optional argument max-width specifies a maximum width and
defaults to the width of window’s frame. The optional argument
min-width specifies a minimum width and defaults to
window-min-width. Both max-width and min-width are
specified in columns and include any left or right decorations of
window.
The optional argument preserve-size, if non-nil, will
install a parameter to preserve the size of window during future
resize operations (see Preserving Window Sizes).
If the option fit-frame-to-buffer (see below) is non-nil,
this function will try to resize the frame of window to fit its
contents by calling fit-frame-to-buffer (see below).
If this is non-nil, fit-window-to-buffer can resize
windows horizontally. If this is nil (the default)
fit-window-to-buffer never resizes windows horizontally. If this
is only, it can resize windows horizontally only. Any other
value means fit-window-to-buffer can resize windows in both
dimensions.
If this option is non-nil, fit-window-to-buffer can fit a
frame to its buffer. A frame is fit if and only if its root window is a
live window and this option is non-nil. If this is
horizontally, frames are fit horizontally only. If this is
vertically, frames are fit vertically only. Any other
non-nil value means frames can be resized in both dimensions.
If you have a frame that displays only one window, you can fit that
frame to its buffer using the command fit-frame-to-buffer.
This command adjusts the size of frame to display the contents of its buffer exactly. frame can be any live frame and defaults to the selected one. Fitting is done only if frame’s root window is live.
The arguments max-height, min-height, max-width and
min-width, if non-nil, specify bounds on the new body size
of frame’s root window. A non-nil value specified by any
of these arguments overrides the corresponding value specified by
the option fit-frame-to-buffer-sizes described below.
If the optional argument only is vertically, this function
may resize the frame vertically only. If only is
horizontally, it may resize the frame horizontally only.
The behavior of fit-frame-to-buffer can be controlled with the
help of the two options listed next.
This option can be used to specify margins around frames to be fit by
fit-frame-to-buffer. Such margins can be useful to avoid, for
example, that the resized frame overlaps the taskbar or parts of its
parent frame.
It specifies the numbers of pixels to be left free on the left, above,
the right, and below a frame that shall be fit. The default specifies
nil for each which means to use no margins. The value specified
here can be overridden for a specific frame by that frame’s
fit-frame-to-buffer-margins parameter, if present.
This option specifies size boundaries for fit-frame-to-buffer.
It specifies the maximum and minimum lines and maximum and minimum
columns of the root window’s body of any frame that shall be fit to its
buffer. Any value this option specifies will be overridden by the
corresponding argument of fit-frame-to-buffer, if non-nil.
This command attempts to reduce window’s height as much as
possible while still showing its full buffer, but no less than
window-min-height lines. The return value is non-nil if
the window was resized, and nil otherwise. If window is
omitted or nil, it defaults to the selected window. Otherwise,
it should be a live window.
This command does nothing if the window is already too short to display all of its buffer, or if any of the buffer is scrolled off-screen, or if the window is the only live window in its frame.
This command calls fit-window-to-buffer (see above) to do its
work.
This function balances windows in a way that gives more space to full-width and/or full-height windows. If window-or-frame specifies a frame, it balances all windows on that frame. If window-or-frame specifies a window, it balances only that window and its siblings (see Windows and Frames).
This function attempts to give all windows on the selected frame approximately the same share of the screen area. Full-width or full-height windows are not given more space than other windows.
This function attempts to make window as large as possible, in
both dimensions, without resizing its frame or deleting other windows.
If window is omitted or nil, it defaults to the selected
window.
This function attempts to make window as small as possible, in
both dimensions, without deleting it or resizing its frame. If
window is omitted or nil, it defaults to the selected
window.