Function: display-buffer-in-previous-window

Display BUFFER in a window previously showing it.
If ALIST has a non-nil `inhibit-same-window' entry, the selected
window is not eligible for reuse.

If ALIST contains a `reusable-frames' entry, its value determines
which frames to search for a reusable window:
nil -- the selected frame (actually the last non-minibuffer frame)
A frame -- just that frame
`visible' -- all visible frames
0 -- all frames on the current terminal
t -- all frames.

If ALIST contains no `reusable-frames' entry, search just the
selected frame if `display-buffer-reuse-frames' and
`pop-up-frames' are both nil; search all frames on the current
terminal if either of those variables is non-nil.

If ALIST has a `previous-window' entry, the window specified by
that entry will override any other window found by the methods above, even if that window never showed BUFFER before.