rrdgraph(1): Document the RRDCACHED_ADDRESS environment variable.

diff --git a/doc/rrdgraph.pod b/doc/rrdgraph.pod
index c8fe0e0..262410e 100644 (file)
--- a/doc/rrdgraph.pod
+++ b/doc/rrdgraph.pod
@@ -478,6 +478,21 @@ There is more information returned than in the standard interface.
 Especially the 'graph_*' keys are new. They help applications that want to
 know what is where on the graph.
 
+=head1 ENVIRONMENT VARIABLES
+
+The following environment variables may be used to change the behavior of
+C<rrdtoolE<nbsp>graph>:
+
+=over 4
+
+=item B<RRDCACHED_ADDRESS>
+
+If this environment variable is set it will have the same effect as specifying
+the C<--daemon> option on the command line. If both are present, the command
+line argument takes precedence.
+
+=back
+
 =head1 SEE ALSO
 
 L<rrdgraph> gives an overview of how B<rrdtool graph> works.