These functions access and select minibuffer windows and test whether they are active.
This function returns the currently active minibuffer window, or
nilif there is none.
This function specifies window as the minibuffer window to use. This affects where the minibuffer is displayed if you put text in it without invoking the usual minibuffer commands. It has no effect on the usual minibuffer input functions because they all start by choosing the minibuffer window according to the current frame.
This function returns non-
nilif window is a minibuffer window. window defaults to the selected window.
It is not correct to determine whether a given window is a minibuffer by
comparing it with the result of
there can be more than one minibuffer window if there is more than one