mbtowc : mbtowc « stdlib.h « C Tutorial

Item	Value
Header file	stdlib.h
Declaration	int mbtowc(wchar_t out, const char in, size_t size);
Function	converts the multibyte character in into its wide-character equivalent out. Only size number of characters will be examined.
Return	returns the number of bytes that are put into *out or -1 or error. If in is null, then mbtowc() returns nonzero if multibyte characters have state-dependent encodings. If they do not, zero is returned.

#include <stdlib.h>
#include <stdio.h>

int main(void){

  char *mb = "asdfadsf";
  char str[1000];

  mbtowc(str, mb, 2);
 
  printf("%s",str);

}

23.22.mbtowc
	23.22.1.	mbtowc