Arbortext Command Language > set Command Options > set prefersystemid
  
set prefersystemid
set prefersystemid= { on | off}
This command determines whether the system identifier (if on) or public identifier and entity name (if off) is given priority when searching a catalog file to resolve an entity. The default is off, meaning that the public identifier and entity name are preferred over the system identifier.
* 
If you set this preference to prefer system IDs, or set prefer=”system” in your catalogs, be sure to have system entries map all http URIs to local files. For example, a document type declaration such as “<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">” would cause a request to be sent to the W3C servers if no system entry was provided for the URI.