4.6 Influencing runtime behavior

These options affect the runtime behavior of gfortran.

-fconvert=conversion

Specify the representation of data for unformatted files. Valid values for conversion are: `native', the default; `swap', swap between big- and little-endian; `big-endian', use big-endian representation for unformatted files; `little-endian', use little-endian representation for unformatted files.

This option has an effect only when used in the main program. The CONVERT specifier and the GFORTRAN_CONVERT_UNIT environment variable override the default specified by -fconvert.

-frecord-marker=length

Specify the length of record markers for unformatted files. Valid values for length are 4 and 8. Default is whatever off_t is specified to be on that particular system. Note that specifying length as 4 limits the record length of unformatted files to 2 GB. This option does not extend the maximum possible record length on systems where off_t is a four_byte quantity.