If you use the interactive version of the gen option, you are immediately given the opportunity to store the session in a file, so that your responses can be used again. (In fact, you can use the session file as the list file with the non-interactive version of gen.) If you indicate that you do want to save the session, you are prompted for a session file name.
Next you are prompted for the name of the new file, and for its attributes. The exact prompts are shown here, and are described in Specifying File Attributes in Advance. Default values are enclosed in brackets.
Save this session [Y]? Enter session filename: Enter filename: Enter the blocking factor [1]: Enter the number of blocks to pre-allocate [1]: Enter the # of blocks for extension [0]: Enter the compression factor (0-100) [0]: Enable record encryption [N]? Enter the maximum record size: Enter the minimum record size (1-maximum) [maximum]: Enter the # of keys [1]: -- Primary key -- Enter number of segments (1-6): (For generating Version 3 files) Enter number of segments (1-16): (For generating Version 4 or 5 files) Enter segment size: Enter segment offset:(Segment size and offset repeat as a pair for each segment) Duplicates allowed [N]? -- Alternate key n -- (repeats for each alternate key) Enter number of segments: Duplicates allowed [N]? Enter segment size: Enter segment offset:(Segment size and offset repeat as a pair for each segment) Enter translation table filename: Enter file comment (30 char max): Generate another file?