Run Simulation until specified src src_mac, dst_mac or eth_type is discovered in the network stream by the link.
If timeout is a positive number, the command will run for at most that many seconds of virtual time.
If timeout-rt is a positive number, the command will run for at most that many seconds of real time.
A time-out will be signaled by throwing a CLI exception, which can be captured using try/except in order to take specific action, or to let it pass unhandled.