This function block of the ⇘ CAA_File.library returns the path for the root directory.
Output:
| 
                               xDone  | 
                           
                               BOOL  | 
                           
                               see: ⇘ “CAA 指南”  | 
                        
| 
                               xBusy  | 
                           
                               BOOL  | 
                           
                               see: ⇘ “CAA 指南”  | 
                        
| 
                               xError  | 
                           
                               BOOL  | 
                           
                               see: ⇘ “CAA 指南”  | 
                        
| 
                               eError  | 
                           
                               FILE.ERROR  | 
                           
                               Error ID  | 
                        
| 
                               sFileName  | 
                           
                               CAA.FILENAME  | 
                           
                               Root directory name with drive specification  |