Two runtime elements in a run unit can reference common file connectors in the following circumstances: 
               
            
 
            
             
               	 
               - An external file connector can be referenced from any runtime element which describes that file connector. 
                  	 
               
- If a program is contained in another program, both programs can refer to a common file connector by referring to an associated
                  global file-name either in the containing program or in any program which directly or indirectly contains the containing program.