tool-bar-lines-needed

tool-bar-lines-needed is an alias for `tool-bar-height' in `frame.el'.

(tool-bar-lines-needed &optional FRAME PIXELWISE)

Return the number of lines occupied by the tool bar of FRAME.
If FRAME is nil or omitted, use the selected frame. Optional argument
PIXELWISE non-nil means return the height of the tool bar in pixels.