rem: store_char (int c)
add: store_char (char c)
context: store_char (int c){  if (buff_current >= buff_allocated)    {      /* May be too generous. */      buff_allocated = 2 * buff_allocated;      buff = (char *) xrealloc (buff, buff_allocated * sizeof (char));    }  buff[buff_current++] = (char) c;}