wake on lan

if target IP == 192.168.0.4,    target MAC == 01:23:45:67:89:ab

1> {ok,S}=gen_udp:open(0,[{broadcast,true}]).


2>  gen_udp:send(S, {192,168,0,4},  9,  <<16#0123456789ab>>).

or 

2>  gen_udp:send(S, "192.168.0.4",  9,  <<16#0123456789ab>>).