$ ef -h
Usage: ef [options] <command> args [<command> args]...

The ef (easy frame) tool allow to easily transmit frames, and
optionally specify what frames it expect to receive.

Options:
  -h                    Top level help message.
  -t <timeout-in-ms>    When listening on an interface (rx),
     When listening on an interface (rx), the tool will always
     listen during the entire timeout period. This is needed,
     as we must also check that no frames are received during
     the test.  Default is 100ms.

  -c <if>,[<snaplen>],[<sync>],[<file>],[cnt]
     Use tcpdump to capture traffic on an interface while the
     test is running. If file is not specified, then it will
     default to './<if>.pcap'
     tcpdump will be invoked with the following options:
     tcpdump -i <if> [-s <snaplen>] [-j <sync>] -w <file> -c <cnt>


Valid commands:
  tx: Transmit a frame on a interface. Syntax:
  tx <interface> FRAME | help

  rx: Specify a frame which is expected to be received. If no 
      frame is specified, then the expectation is that no
      frames are received on the interface. Syntax:
  rx <interface> [FRAME] | help

  hex: Print a frame on stdout as a hex string. Syntax:
  hex FRAME

  name: Specify a frame, and provide a name (alias) for it.
        This alias can be used other places instead of the
        complete frame specification. Syntax:
  name <name> FRAME-SPEC | help

  pcap: Write a frame to a pcap file (appending if the file
  exists already). Syntax:
  pcap <file> FRAME | help

Where FRAME is either a frame specification of a named frame.
Syntax: FRAME ::= FRAME-SPEC | name <name>

FRAME-SPEC is a textual specification of a frame.
Syntax: FRAME-SPEC ::= [HDR-NAME [<HDR-FIELD> <HDR-FIELD-VAL>]...]...
        HDR-NAME ::= eth|stag|ctag|arp|ipv4|udp

Examples:
  ef tx eth0 eth dmac ::1 smac ::2 stag vid 0x100 ipv4 dip 1 udp

  ef name f1 eth dmac ff:ff:ff:ff:ff:ff smac ::1\
     rx eth0 name f1\
     tx eth1 name f1

A complete header or a given field in a header can be ignored by
using the 'ign' or 'ignore' flag.
Example:
  To ignore the ipv4 header completly:
  ef hex eth dmac 1::2 smac 3::4 ipv4 ign udp

  To ignore the ipv4 everything in the ipv4 header except the sip:
  ef hex eth dmac 1::2 smac 3::4 ipv4 ign sip 1.2.3.4 udp

  To ignore the sip field in ipv4:
  ef hex eth dmac 1::2 smac 3::4 ipv4 sip ign udp

A frame can be repeated to utilize up to line speed bandwith (>512 byte frames)
using the 'rep' or 'repeat' flag.
Example:
   Send a frame 1 million times:
   ef tx eth0 rep 1000000 eth dmac ::1 smac ::2
   Note that the repeat flag must follow the tx <interface> key-word
   Results must be viewed through the PC or DUT interface counters, i.e. outside of 'ef'

$ mkdir build
$ cd build
$ cmake ..
$ make
$ sudo make install