Availability:C-language interface function
int SwriteBOM(IOSTREAM
*s)This function writes a Byte Order Mark (BOM) to s
and should be called immediately after opening a stream for writing. If
the encoding is one of ENC_UTF8, ENC_UNICODE_BE
or
ENC_UNICODE_LE it writes the code point \ufeff
(a zero-width white space) to the stream in the current encoding and
sets the SIO_BOM flag on the stream.