Examples of tcpick usage
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connection status
=================

Tcpick is a sniffer able to understand wich status has the connection (SYN-SENT, SYN-RECEIVED and so on). To see the connection tracker in action on eth0 simply type:

     # tcpick -i eth0 -C

`-C' means ``enable colors'', and the output is very pretty.

You will see something like this:

     23:07:42.672171  1      SYN-SENT       12.34.56.78:41599 > 123.123.123.123:http
     23:07:42.822239  2      SYN-SENT       12.34.56.78:41600 > 32.13.21.32:5973
     23:07:42.826634  3      SYN-SENT       12.34.56.78:41601 > 123.45.67.89:5555
     23:07:42.854681  4      SYN-SENT       12.34.56.78:41602 > 1.2.3.4:56789
     23:07:43.084242  1      SYN-RECEIVED   12.34.56.78:41599 > 123.123.123.123:http
     23:07:43.087045  1      ESTABLISHED    12.34.56.78:41599 > 123.123.123.123:http
     23:07:44.061311  5      SYN-SENT       12.34.56.78:41603 > 10.20.30.40:8888

display the payload and packet headers
======================================

It is very easy:

     # tcpick -i eth0 -C -yP -h -a

`-yP' means ``payload printable'', `-h' means ``header'' and `-a' means names resolution. Unprintable carachters are displayed as dots.

display client data only of the first smtp connection
=====================================================

     # tcpick -i eth0 -C -bCU -T1 "port 25"

`-bCU' means: display the rebuilded stream (`-b') only the client side (`C') and unprintable carachters will be displayed as hexcode (`U').

`T1' means: display only the first (1) connection.

``port 25'' is the filter.

download a file passively
=========================

Yeah! It is very a simple job:

#tcpick -i eth0 -wR ``port ftp-data''

When the file has been completely transmitted (connection displayed as ``CLOSED'')  check in the working directory: you will find some files named like this:

     # ls *.tcpick
     client_123.45.67.89_98.76.54.32_34567.tcpick
     server_123.45.67.89_98.76.54.32_34567.tcpick

Bingo! If you do `$ file *.tcpick' you will find that one of the two is a a gzip archive or whatever you sniffed.

redirect the first connection to a software
===========================================

You must choose between client or server side, because you don't want both stream mixed in the standard output. It is a really simple job, just type:

     # tcpick -i eth0 --pipe client "port 80" | gzip > http_response.gz

or

     # tcpick -i eth0 --pipe server "port 25" | nc foobar.net 25

Now, use your imagination and let me know what crazy experiments have you done with tcpick ;^)