File processing options

These topics describe several runtime processing options.

• Specify the type of processing
  When you use a file in a program, the system needs to know what type of operation you plan to use for that file. You can specify the type of processing with the OPTION parameter.
• Specify the initial file position
  After the file is opened, the system needs to know where it should start processing the file. You can specify the initial file position with the POSITION parameter.
• Reuse deleted records
  Sometimes you might want to reuse deleted records for your database files. In this case, you can use the REUSEDLT parameter.
• Ignore the keyed sequence access path
  If a key field is defined for the file, the system automatically uses the keyed sequence access path. However, sometimes, you can use the ACCPTH parameter to ignore the keyed sequence access path for better performance.
• Delay end-of-file processing
  When your program reaches the end of the data in a database file, the system normally signals your program that there is no more data to read. If you want the system to hold your program until more data arrives in the file, you can use the EOFDLY parameter to delay the end-of-file processing.
• Specify the record length
  As an option, you can specify the record length in your high-level language program.
• Ignore record formats
  When you use a multiple format logical file, the system assumes that you want to use all formats defined for that file. However, if you do not want to use all of the formats, you can specify which formats you want to use and which ones you want to ignore.
• Determine if duplicate keys exist
  The set of keyed sequence access paths used to determine if the key is a duplicate key differs depending on the input/output (I/O) operation that is performed. You can determine if duplicate keys exist using the DUPKEYCHK parameter.