This is a Hardware specific function. It is not implemented in the Compiler.
#include <stdlib.h>
int mbtowc(wchar_t *wc, const char *s, size_t n);
mbtowc() converts a multi-byte character s to a wide character code wc. Only the first n bytes of *s are taken into consideration.
The number of bytes of the multi-byte character converted (size_t) if successful or -1 if there was an error.
mblen(), and