Max bytes per flow. The default is to store an unlimited number of bytes per flow. Higher numbers produce more messages. Numbers higher than 10 can produce a large amount of debugging information useful only to developers. Max file descriptors used.
Higher numbers use more system resources, but usually perform better.
The -v option will report how many file descriptors tcpflow is using. Print usage information and exit. Capture packets from the network interface named iface . If no interface is specified with -i , a reasonable default will be used by libpcap automatically. No promiscuous mode.