an integer

n

, where

n

is the fixed length of the field

an asterisk (

*

), indicating a variable-length field

a fixed length field mapping in the form (

starting-position

:

field-length

), where

starting-position

marks the beginning of the field, measured in number of characters from the beginning (or leftmost position) of the record, and

field-length

is the number of characters to include in the field, starting from

starting-position

and counting from left to right.