3.4.123.2 Notes:

This option does not apply to files opened with STATUS="SCRATCH". I/O operations done on these files are always with the byte-order and byte-alignment of the native processor.

The first default, when -xfilebyteorder does not appear on the command line, is -xfilebyteorder=native:%all.

A file name or unit number can be declared only once in this option.

When -xfilebyteorder does appear on the command line, it must appear with at least one of the little, big, or native specifications.

Files not explicitly declared by this flag are assumed to be native files. For example, compiling with -xfilebyteorder=little4:zork.out declares zork.out to be a little-endian 32-bit x86 file with a 4-byte maximum data alignment. All other files in the program are native files.

When the byte-order specified for a file is the same as the native processor but a different alignment is specified, the appropriate padding will be used even though no byte swapping is done. For example, this would be the case when compiling with -m64 for 64-bit x86 platforms and -xfilebyteorder=little4:filename is specified.

The declared types in data records shared between big-endian and little-endian platforms must have the same sizes. For example, a file produced by a SPARC executable compiled with -xtypemap=integer:64,real:64,double:128 cannot be read by an x86 executable compiled with -xtypemap=integer:64,real:64,double:64 since the default double precision data types will have different sizes. (However, note that starting with the release of Sun Studio 12 Update 1, double:128 is accepted on x64 processors.)

If an option that changes the alignment of the components within a VAX structure (such as —vax=struct_align) or a derived type (such as —aligncommon or —dalign) is used on one platform, the same alignment option has to be used on other platforms sharing the same unformatted data file whose content is affected by the alignment option.

An I/O operation with an entire UNION/MAP data object on a file specified as non-native will result in a runtime I/O error. You can only execute I/O operations using the individual members of the MAP (and not an entire VAX record containing the UNION/MAP) on non-native files.