UTF16_IS_SURROGATE_FIRST   32 mbstring/oniguruma/enc/utf16_be.c #define UTF16_IS_SURROGATE_FIRST(c)    (c >= 0xd8 && c <= 0xdb)
UTF16_IS_SURROGATE_FIRST   32 mbstring/oniguruma/enc/utf16_le.c #define UTF16_IS_SURROGATE_FIRST(c)    (c >= 0xd8 && c <= 0xdb)