stream_position_data/3stream_position_data(?Field, ?Position, ?Value)
Value is the value of the Field field of stream position object Position.
[byte_count,line_count,character_count,line_position]
Note that byte_count is meaningful only for binary streams and
that the other values are meaningful only for text streams.
Stream position object representing the
current position of Stream.
Can be used to backtrack over the fields.