__strncasecmp (s1, s2, n)
__strncasecmp (s1, s2, n LOCALE_PARAM)
__strncasecmp (s1, s2, n)     const char *s1;     const char *s2;     size_t n;{  const unsigned char *p1 = (const unsigned char *) s1;  const unsigned char *p2 = (const unsigned char *) s2;  unsigned char c1, c2;  if (p1 == p2 || n == 0)    return 0;  do    {      c1 = tolower (*p1++);      c2 = tolower (*p2++);      if (c1 == '\0' || c1 != c2)	return c1 - c2;    } while (--n > 0);  return c1 - c2;}