The Importance of the File Status Key

   All errors in processing a VSAM file, whether logic errors in your program

   or I/O errors on the external storage media, return control to your COBOL

   program.  When an error occurs, the status key value will indicate the

   status of the last request on the file.  Refer to VS COBOL II Application

   Programming Language Reference if you need to know the status key values

   and their meanings for VSAM files.

   Because file problems do not usually cause an abend, it is possible that

   your program will continue executing with invalid information.  Good

   coding practice demands that you check the file status key value after

   every input/output request (including OPEN and CLOSE).  Each VSAM file

   should have its own status key defined in your program.  For more

   information, see "File Status Key" in topic 4.4.3.

   You can also use an ERROR/EXCEPTION declarative for handling input/output

   errors for VSAM files