(Text Terminal Colors): Document tty-display-color-cells.

1 files changed, 10 insertions, 2 deletions

diff --git a/lispref/frames.texi b/lispref/frames.texi
index 345f23a3d85..af03160d992 100644
--- a/lispref/frames.texi
+++ b/lispref/frames.texi
@@ -1551,13 +1551,16 @@ and that name is still supported as an alias.
 @cindex colors on text-only terminals
 
   Emacs can display color on text-only terminals, starting with version
-21.  These terminals support only a small number of colors, and the
-computer uses small integers to select colors on the terminal.  This
+21.  These terminals usually support only a small number of colors, and
+the computer uses small integers to select colors on the terminal.  This
 means that the computer cannot reliably tell what the selected color
 looks like; instead, you have to inform your application which small
 integers correspond to which colors.  However, Emacs does know the
 standard set of colors and will try to use them automatically.
 
+  The functions described in this section control how terminal colors
+are used by Emacs.
+
 @cindex rgb value
   Several of these functions use or return @dfn{rgb values}.  An rgb
 value is a list of three integers, which give the amount of red, the
@@ -1572,6 +1575,11 @@ will specify which terminal to operate on (the default being the
 selected frame's terminal; @pxref{Input Focus}).  At present, though,
 the @var{display} argument has no effect.
 
+@defun tty-display-color-cells &optional display
+This function returns the number of distinct colors supported for
+@var{display}.
+@end defun
+
 @defun tty-color-define name number &optional rgb display
 @tindex tty-color-define
 This function associates the color name @var{name} with