[support] Varnish 2.x debugging

Hello Drupal Lovers I am trying to figure out a way to debug Varnish and write some code in VCL file. I am struggling to get all attributes and properties of an object. Is there anything like print_r for varnish too. I am looking at the request object and object is "req", any way to know what all information does it contain ? Hoping to get a reply soon :) -- Regards, Vaibhav Jain