Next: Switching Buffers, Previous: Cyclic Window Ordering, Up: Windows [Contents][Index]

### 27.11 Buffers and Windows

This section describes low-level functions for examining and setting the contents of windows. See Switching Buffers, for higher-level functions for displaying a specific buffer in a window.

Function: window-buffer &optional window

  This function returns the buffer that window is displaying. If window is omitted or `nil` it defaults to the selected window. If window is an internal window, this function returns `nil`.

Function: set-window-buffer window buffer-or-name &optional keep-margins

  This function makes window display buffer-or-name. window should be a live window; if `nil`, it defaults to the selected window. buffer-or-name should be a buffer, or the name of an existing buffer. This function does not change which window is selected, nor does it directly change which buffer is current (see Current Buffer). Its return value is `nil`.

  If window is strongly dedicated to a buffer and buffer-or-name does not specify that buffer, this function signals an error. See Dedicated Windows.

  By default, this function resets window’s position, display margins, fringe widths, and scroll bar settings, based on the local variables in the specified buffer. However, if the optional argument keep-margins is non-`nil`, it leaves the display margins and fringe widths unchanged.

  When writing an application, you should normally use the higher-level functions described in Switching Buffers, instead of calling `set-window-buffer` directly.

  This runs `window-scroll-functions`, followed by `window-configuration-change-hook`. See Window Hooks.

Variable: buffer-display-count

  This buffer-local variable records the number of times a buffer has been displayed in a window. It is incremented each time `set-window-buffer` is called for the buffer.

Variable: buffer-display-time

  This buffer-local variable records the time at which a buffer was last displayed in a window. The value is `nil` if the buffer has never been displayed. It is updated each time `set-window-buffer` is called for the buffer, with the value returned by `current-time` (see Time of Day).

Function: get-buffer-window &optional buffer-or-name all-frames

  This function returns the first window displaying buffer-or-name in the cyclic ordering of windows, starting from the selected window (see Cyclic Window Ordering). If no such window exists, the return value is `nil`.

  buffer-or-name should be a buffer or the name of a buffer; if omitted or `nil`, it defaults to the current buffer. The optional argument all-frames specifies which windows to consider:

  - `t` means consider windows on all existing frames.
  - `visible` means consider windows on all visible frames.
  - 0 means consider windows on all visible or iconified frames.
  - A frame means consider windows on that frame only.
  - Any other value means consider windows on the selected frame.

  Note that these meanings differ slightly from those of the all-frames argument to `next-window` (see Cyclic Window Ordering). This function may be changed in a future version of Emacs to eliminate this discrepancy.

Function: get-buffer-window-list &optional buffer-or-name minibuf all-frames

  This function returns a list of all windows currently displaying buffer-or-name. buffer-or-name should be a buffer or the name of an existing buffer. If omitted or `nil`, it defaults to the current buffer. If the currently selected window displays buffer-or-name, it will be the first in the list returned by this function.

  The arguments minibuf and all-frames have the same meanings as in the function `next-window` (see Cyclic Window Ordering). Note that the all-frames argument does not behave exactly like in `get-buffer-window`.

Command: replace-buffer-in-windows &optional buffer-or-name

  This command replaces buffer-or-name with some other buffer, in all windows displaying it. buffer-or-name should be a buffer, or the name of an existing buffer; if omitted or `nil`, it defaults to the current buffer.

  The replacement buffer in each window is chosen via `switch-to-prev-buffer` (see Window History). Any dedicated window displaying buffer-or-name is deleted if possible (see Dedicated Windows). If such a window is the only window on its frame and there are other frames on the same terminal, the frame is deleted as well. If the dedicated window is the only window on the only frame on its terminal, the buffer is replaced anyway.

Next: Switching Buffers, Previous: Cyclic Window Ordering, Up: Windows [Contents][Index]