#include <fontconfig.h>
int FcUtf16ToUcs4 (FcChar8 *src, FcEndianendian, FcChar32 *dst, intlen);
Converts the next Unicode char from src into dst and returns the number of bytes containing the char. src must be at least len bytes long. Bytes of src are combined into 16-bit units according to endian.
Fontconfig version 2.3.2