The result is a Number, which is the number of the buffer associated with window {nr}. {nr} can be the window number or the |window-ID|. When {nr} is zero, the number of the buffer in the current window is returned. When window {nr} doesn't exist, -1 is returned. Example: :echo "The file in the current window is " . bufname(winbufnr(0)) Can also be used as a |method|: FindWindow()->winbufnr()->bufname()