def rename(fromname, toname)
      resp = sendcmd("RNFR " + fromname)
      if resp[0] != ?3
        raise FTPReplyError, resp
      end
      voidcmd("RNTO " + toname)
    end
def rename(fromname, toname)
      resp = sendcmd("RNFR " + fromname)
      if resp[0] != ?3
        raise FTPReplyError, resp
      end
      voidcmd("RNTO " + toname)
    end
Renames a file on the server.