Use the Optimal Record Type

Unless a certain record type is needed for portability reasons, choose the most efficient type, as follows:

• For sequential files of a consistent record size, the fixed-length record type gives the best performance.
• For sequential unformatted files when records are not fixed in size, the variable-length record type gives the best performance, particularly for BACKSPACE operations.
• For sequential formatted files when records are not fixed in size, the Stream_LF record type gives the best performance.

For more information:

• On OPEN statement specifiers and defaults, see OPEN Statement and OPEN.
• On Visual Fortran data files, see Devices and Files.