window-with-parameter

window-with-parameter is a compiled Lisp function in `window.el'.

(window-with-parameter PARAMETER &optional VALUE FRAME ANY MINIBUF)

Return first window on FRAME with PARAMETER non-nil.
FRAME defaults to the selected frame. Optional argument VALUE
non-nil means only return a window whose window-parameter value
for PARAMETER equals VALUE (comparison is done with `equal').
Optional argument ANY non-nil means consider internal windows
too.

Optional argument MINIBUF t means consider FRAME's minibuffer
window even if it isn't active. MINIBUF nil or omitted means
consider FRAME's minibuffer window only if it's active. In both
cases the minibuffer window must be part of FRAME. MINIBUF
neither nil nor t means never consider the minibuffer window.