Using Externally Described Disk Files

Externally described DISK files are identified by an E in position 22 of the file description specifications. The E indicates that the compiler is to retrieve the external description of the file from the system when the program is compiled. Therefore, you must create the file before the program is compiled.

The external description for a DISK file includes:

• The record-format specifications that contain a description of the fields in a record
• Access path specifications that describe how the records are to be retrieved.

These specifications result from the DDS for the file and the IBM i create file command that is used for the file.