Functions for displaying a buffer can be told to not use specific windows by marking these windows as dedicated to their buffers.
display-buffer (see Choosing Window) never uses a dedicated window for displaying another buffer in it.
get-largest-window (see Cyclic Window Ordering) do not consider dedicated windows as candidates when their
dedicated argument is non-
nil. The behavior of
set-window-buffer (see Buffers and Windows) with respect to dedicated windows is slightly different, see below.
Functions supposed to remove a buffer from a window or a window from a frame can behave specially when a window they operate on is dedicated. We will distinguish three basic cases, namely where (1) the window is not the only window on its frame, (2) the window is the only window on its frame but there are other frames on the same terminal left, and (3) the window is the only window on the only frame on the same terminal.
delete-windows-on (see Deleting Windows) handles case (2) by deleting the associated frame and case (3) by showing another buffer in that frame’s only window. The function
replace-buffer-in-windows (see Buffers and Windows) which is called when a buffer gets killed, deletes the window in case (1) and behaves like
bury-buffer (see Buffer List) operates on the selected window (which shows the buffer that shall be buried), it handles case (2) by calling
frame-auto-hide-function (see Quitting Windows) to deal with the selected frame. The other two cases are handled as with
function window-dedicated-p \&optional window
This function returns non-
window is dedicated to its buffer and
nil otherwise. More precisely, the return value is the value assigned by the last call of
nil if that function was never called with
window as its argument. The default for
window is the selected window.
function set-window-dedicated-p window flag
This function marks
window as dedicated to its buffer if
flag is non-
nil, and non-dedicated otherwise.
As a special case, if
window becomes strongly dedicated to its buffer.
set-window-buffer signals an error when the window it acts upon is strongly dedicated to its buffer and does not already display the buffer it is asked to display. Other functions do not treat
t differently from any non-
You can also tell
display-buffer to mark a window it creates as dedicated to its buffer by providing a suitable
dedicated action alist entry (see Buffer Display Action Alists).