DEFVAR_PER_BUFFER ("line-spacing",
¤t_buffer->extra_line_spacing, Qnil,
doc: /* Additional space to put between lines when displaying a buffer.
-The space is measured in pixels, and put below lines on window systems.
+The space is measured in pixels, and put below lines on graphic displays,
+see `display-graphic-p'.
If value is a floating point number, it specifies the spacing relative
to the default frame line height. A value of nil means add no extra space. */);