Document enum, altenum, and mask

Signed-off-by: Peter Harris <pharris@opentext.com>

diff --git a/doc/xml-xcb.txt b/doc/xml-xcb.txt
index 5d34754..feb9984 100644 (file)
--- a/doc/xml-xcb.txt
+++ b/doc/xml-xcb.txt
@@ -178,6 +178,12 @@ separated by a single colon.  For example, to refer to the PIXMAP type defined
 in glx rather than the one defined in xproto, use type="glx:PIXMAP" rather
 than type="PIXMAP".
 
+Note: Most of the below may optionally contain an enum, altenum, or mask
+attribute, which follows the above rules for "type". "enum" is an exhaustive
+enum; the value is restricted to one of the constants named in the enum.
+"altenum" may be one of the values contained in the enum, but it need not be.
+"mask" refers to an enum to be used as a bitmask.
+
 <pad bytes="integer" />
 
   This element declares some padding in a data structure.  The bytes