Only device types DISK and DATABASE can be opened for I-O.
The file is opened for both input and output operations. The file position indicator is set to the first record in the file. If no records exist in the file, the file position indicator is set so that processing of the first sequential READ statement results in an AT END condition.
The first record to be made available to the program can be specified at run time by using the POSITION parameter on the OVRDBF CL command. For more information on this command, see the CL and APIs section of the Programming category in the IBM® i Information Center at this Web site - http://www.ibm.com/systems/i/infocenter/.