packet capture and display tool
usage:
$ fx sniff wlan capture packets over WLAN interface,
and show their summaries
$ fx sniff --view hex eth capture packets over Ethernet interface,
and show their hexadecimal dump
$ fx sniff --view wireshark wlan capture packets over WLAN interface,
and start wireshark GUI for display
$ fx sniff --file myfile eth capture packets and store
at //out/myfile.pcapng
$ fx sniff -t 10 wlan capture for 10 sec
$ fx sniff --help show all command line options