Document Types > Document Types > Catalog Files > Using Public or System Identifiers
  
Using Public or System Identifiers
As a default, Arbortext products will give priority to the public identifier and entity name when searching a catalog file to resolve an entity. To confirm that system identifiers should be preferred instead, set one of the following:
set prefersystemid=on preference
set prefersystemidxmlcatalogs=on preference (for XML catalogs)
prefer=”system” in catalogs
For more information, see the Arbortext Command Language Reference PDF.
If you use one of these methods, be sure that 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 send a request to the W3C servers if no system entry was provided for the URI.