Ensuring that file attributes match your program

When the fixed file attributes in the DD statement or the data-set label and the attributes that are coded for that file in the SELECT clause and FD entry are not consistent, an OPEN statement in your program might not work.

Mismatches in the attributes for file organization, record format (fixed or variable), record length, or the code set result in file status code 39 and the failure of the OPEN statement. An exception exists for files in the z/OS® UNIX file system: mismatches in record format and record length do not cause an error.

To prevent common file status 39 problems, follow the guidelines for processing existing or new files.

If you have not made a file available with a DD statement or a TSO ALLOCATE command, and your COBOL program specifies that the file be created, Enterprise COBOL dynamically allocates the file. When the file is opened, the file attributes that are coded in your program are used. You do not have to worry about file attribute conflicts.

Remember that information in the JCL or environment variable overrides information in the data-set label.

related references  
FILE SECTION entries