Define the Operation Codes and FCD

Before you create or open a file, you must set up a data area for the file's FCD. For ease of use, this program also sets up a number of pre-defined operation code values that you can call upon.

  1. In the working-storage section of your program, paste the following code:
           01  opcode                       pic x(2).
             78  OP-QUERY-FILE              value x"0006".
             78  OP-OPEN-INPUT              value x"fa00".
             78  OP-OPEN-OUTPUT             value x"fa01".
             78  OP-OPEN-I-O                value x"fa02".
             78  OP-WRITE                   value x"faf3".
             78  OP-RELEASE                 value x"faf3".
             78  OP-REWRITE                 value x"faf4".
             78  OP-READ-NEXT               value x"faf5".
             78  OP-START-EQUAL             value x"fae9".
             78  OP-CLOSE                   value x"fa80".

    The opcode variable will be used throughout the running of this example, each time using one of the level-78 constant values shown to perform a specific operation.

  2. Just beneath the op codes, still in the working-storage section, paste the following code:
           01 fcd.
               copy "xfhfcd3.cpy".    

    xfhfcd3.cpy is a copybook that is supplied with your product, defining all the possible fields that you may use to set up the FCD for the file that you will create. The tutorial will only use a small selection of the fields available.

  3. Press Ctrl+S to save the changes so far.
Next you'll define the name of the data file that you will create.