Mention initialization feature of agattr().

diff --git a/lib/cgraph/cgraph.3 b/lib/cgraph/cgraph.3
index 508d7e5e443fcff086313e157dbcd6ea3a33302d..9e345c0e51c969789be4e65df47d2480ced8595f 100644 (file)
--- a/lib/cgraph/cgraph.3
+++ b/lib/cgraph/cgraph.3
@@ -256,7 +256,9 @@ Otherwise, if the attribute already exists, its default
 for creating new objects is set to the given value;
 if it does not exist, a new attribute is created with the
 given default, and the default is applied to all pre-existing
-objects of the given kind. \fBagattrsym\fP is a helper function
+objects of the given kind. If \fBg\fP is NIL, the default is
+set for all graphs created subsequently.
+\fBagattrsym\fP is a helper function
 that looks up an attribute for a graph object given as an argument.
 \fBagnxtattr\P permits traversing the list of attributes of
 a given type.  If \fBNIL\fP is passed as an argument it gets