https://docs.oracle.com/cd/E88353_01/html/E37855/uconv-u16tou8-9f.html
uconv_u16tou8 - man pages section 9: DDI and DKI Kernel Functions
uconv_u16tou32 , uconv_u16tou8 , uconv_u32tou16 , uconv_u32tou8 , uconv_u8tou16 , uconv_u8tou32 - Unicode encoding conversion functions
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