rem: memmove (dest, source, length) char *dest; const char *source; unsigned length;
add: memmove (void *dest0, void const *source0, size_t length)
context: memmove (dest, source, length)     char *dest;     const char *source;     unsigned length;{  char *d0 = dest;  if (source < dest)    /* Moving from low mem to hi mem; start at end.  */    for (source += length, dest += length; length; --length)      *--dest = *--source;  else if (source != dest)    {      /* Moving from hi mem to low mem; start at beginning.  */      for (; length; --length)	*dest++ = *source++;    }  return (void *) d0;}