Program-described files are files whose records and fields are described
on input/output specifications in the program that uses the file. To use a
program-described file in an RPG program you must:
Identify the file(s) in the file description specifications.
If it is a global input file, describe the record and fields
in the input specifications. The file name in positions 7 through 16 in the
input specifications must be the same as the corresponding name entered in
the file specifications.
On the record-identification entries you indicate
whether you want to perform sequence checking of records within the file.
Enter the same file name as in step 1 in the FACTOR
2 field of those calculation specifications which require it. For example,
WRITE operations to a program-described file require a data structure name
in the result field.
If it is a global output file, describe the record and fields
in the output specifications. In addition, you specify how the output is to
be printed. The file name in positions 7 through 16 in the output specifications
must be the same as the corresponding name entered in the file specifications.
A program-described file must exist on the system, and be in your library
list, before the program can run. To create a file, use one of the Create
File commands, which can be found in the CL and APIs section
of the Programming category in the System i Information Center at this Web site - http://www.ibm.com/systems/i/infocenter/.