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Byte Order Mark (BOM)

Older versions of UTF-8 mode in xfst could not accommodate the initial Byte Order Mark that some UTF-8 editors automatically insert to the beginning of a file.

What is a Byte Order Mark?

Besides UTF-8, there are other UTFs (Unicode Transport Format). In some of them bytes are interpreted differently depending on whether the machine is “big-endian” (Sun, MacOSX on PPC) or “little-endian” (Windows, most Linux machines, and MacOSX on INtel machines). for this reason the Unicode standard specifies that a file may begin with a BOM, a sequence of reserved bytes that indicate byte order as well as the type of UTF encoding. But the UTF-8 standard (by far the most common UTF) is the same for both big-endian and little-endian machines. No BOM is needed in a UTF-8 file. Some UTF-8 editors insert a BOM, some don’t. It does not indicate byte order; it just serves to indicate that the encoding is UTF-8 rather than something else.