do_stream

doc/sphinx/reference/vcl.rst

@@ -647,6 +647,12 @@ The following variables are available after the requested object has
 been retrieved from the backend, before it is entered into the cache. In
 other words, they are available in vcl_fetch:
 
+beresp.do_stream 
+  Deliver the object to the client directly without fetching the whole
+  object into varnish. If this request is pass'ed it will not be
+  stored in memory. As of Varnish Cache 3.0 the object will marked as busy
+  as it is delivered so only client can access the object.
+
 beresp.do_esi
   Boolean. ESI-process the object after fetching it. Defaults to false. Set it
   to true to parse the object for ESI directives.