the new data value to be stored in the line referenced by line-ptr. This string may be entered as a list of comma delimited values. If so, they will be concatenated with a space between each entry.
Returns:
Both num-var and RC will be 0 and Msg$ will be "" (Null) for successful completion
Both num-var and RC will be 8 and Msg$ set to an error message on failure (e.g. invalid line pointer)