The file description comprises information concerning the physical structure, identification, and record-names pertaining
                  to a given file. 
                  
 
            
             
               	 
               It determines the internal or external attributes of a file connector, of the associated data records, and of the associated
                  data items. The file description entry also determines whether a file-name is a local name or a global name. 
                  	 
               
 
               
              
            
            
               General Formats for Format 1 (Record Sequential Files)
 
               	  
               	  
 
               
              
            
            
               General Formats for Format 2 (Line Sequential Files)
 
               	  
               	  
 
               
              
            
            
               General Formats for Format 3 (Relative and Indexed Files)
 
               	  
               	  
 
               
              
            
            
               General Formats for Format 4 (Sort-Merge Files)
 
               	  
               	  
 
               
              
            
            
               Syntax Rules for All Formats (All Files)
 
               	  
                
                  	 
                  - The clauses which follow file-name-1 may appear in any order. 
                     	 
                  
- If the VALUE OF FILE-ID clause is specified, literal-1 must be a nonnumeric literal and cannot be a figurative constant. 
                     	 
                  
  
            
            
               Syntax Rules for Formats 1, 2 and 3 (RecordSequential, 
                  		 Line Sequential, Relative and Indexed Files)
 Line Sequential, Relative and Indexed Files)
               
 
               	  
                
                  	 
                  - The level indicator FD identifies the beginning of a file description and must precede the file-name. 
                     	 
                  
- One or more record description entries must follow the file description entry. 
                     	 
                  
- The EXTERNAL clause and the THREAD-LOCAL clause must not be specified in the same file description entry. 
                     	 
                  
  
            
            
               Syntax Rules for Format 4 (Sort-Merge Files) 
 
               	  
                
                  	 
                  - The level indicator SD identifies the beginning of the sort-merge file description and must precede the file-name. 
                     	 
                  
- The clauses which follow the name of the file are optional and may appear in any order. 
                     	 
                  
- One or more record description entries must follow the sort-merge file description entry. However, no input-output statements
                     can be executed for this file. 
                     	 
                  
  
            
            
               General Rules for Format 1 (Record Sequential Files)
 
               	  
                
                  	 
                  - If the file description entry for a sequential file contains the LINAGE clause and the EXTERNAL clause, the LINAGE-COUNTER
                     data item is an external data item. If the file description entry for a sequential file contains the LINAGE clause and the
                     GLOBAL clause, the special register LINAGE-COUNTER is a global name.