FREE_BUF(f->_IO_buf_base);
FREE_BUF(f->_IO_buf_base, _IO_blen (f));
DEFUN(_IO_setb, (f, b, eb, a),      _IO_FILE *f AND char *b AND char *eb AND int a){  if (f->_IO_buf_base && !(f->_flags & _IO_USER_BUF))    FREE_BUF(f->_IO_buf_base);  f->_IO_buf_base = b;  f->_IO_buf_end = eb;  if (a)    f->_flags &= ~_IO_USER_BUF;  else    f->_flags |= _IO_USER_BUF;}