BtrvGetNext
BtrvGetNext (DataVar,Key,Handle)
BtrvGetNext goes to the next record of the file based on the key number
that you pass and reads the record into DataVar. This allows you to
access that database in the sorted order of the key. DataVar is a
MarxMenu variable and the data read creates an array of the fields
stored on disk.
Result Codes:
6 - Invalid Key Number
7 - Different Key Number
9 - End of File
