[support] Add fields to relation types programmatically

[City Boy]

Does anyone know how to add some relation types fields on module install?Is it the same way as the fields of custom content types which created by two functions field_create_field/field_create_instance? I can create relation type,but don't know how to add fields to it.Any help would be appreciated.Cheers, 		 	   		  
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.drupal.org/pipermail/support/attachments/20131104/7a03ee15/attachment.html