text: #include <ctype.h>
  #include <wctype.h>
  #include <stdio.h>
  #include <locale.h>
  
  /**
   * Returns the number of bytes in a multibyte string.
   */
  size_t mbrlen(const char *s, size_t n, mbstate_t *ps) {
      fprintf(stderr, "%s unimplemented", __PRETTY_FUNCTION__);
      return 0;
  }
  