The fringe bitmaps are the actual bitmaps which represent the logical fringe indicators for truncated or continued lines, buffer boundaries, overlay arrows, etc. Each bitmap is represented by a symbol. These symbols are referred to by the variable fringe-indicator-alist, which maps fringe indicators to bitmaps (see Fringe Indicators), and the variable fringe-cursor-alist, which maps fringe cursors to bitmaps (see Fringe Cursors).
Lisp programs can also directly display a bitmap in the left or
right fringe, by using a
display property for one of the
characters appearing in the line (see Other Display Specs). Such
a display specification has the form
(fringe bitmap [face])
fringe is either the symbol
right-fringe. bitmap is a symbol identifying the bitmap
to display. The optional face names a face whose foreground
color is used to display the bitmap; this face is automatically merged
Here is a list of the standard fringe bitmaps defined in Emacs, and how they are currently used in Emacs (via fringe-indicator-alist and fringe-cursor-alist):
Used to indicate truncated lines.
Used to indicate continued lines.
The former is used by overlay arrows. The latter is unused.
Used to indicate buffer boundaries.
Used for different types of fringe cursors.
Not used by core Emacs features.
The next subsection describes how to define your own fringe bitmaps.
fringe-bitmaps-at-pos&optional pos window
This function returns the fringe bitmaps of the display line
containing position pos in window window. The return
value has the form
(left right ov), where left
is the symbol for the fringe bitmap in the left fringe (or
if no bitmap), right is similar for the right fringe, and ov
nil if there is an overlay arrow in the left fringe.
The value is
nil if pos is not visible in window.
If window is
nil, that stands for the selected window.
If pos is
nil, that stands for the value of point in