TShark is a terminal oriented version of Wireshark designed for capturing and displaying packets when an interactive user interface isn't necessary or available. It supports the same options as wireshark. For more information on tshark, see the manual pages (man tshark).
Example D.1. Help information available from tshark
TShark 1.9.3 (SVN Rev 48842 from /trunk) Dump and analyze network traffic. See http://www.wireshark.org for more information. Copyright 1998-2013 Gerald Combs <firstname.lastname@example.org> and contributors. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. Usage: tshark [options] ... Capture interface: -i <interface> name or idx of interface (def: first non-loopback) -f <capture filter> packet filter in libpcap filter syntax -s <snaplen> packet snapshot length (def: 65535) -p don't capture in promiscuous mode -I capture in monitor mode, if available -B <buffer size> size of kernel buffer (def: 1MB) -y <link type> link layer type (def: first appropriate) -D print list of interfaces and exit -L print list of link-layer types of iface and exit Capture stop conditions: -c <packet count> stop after n packets (def: infinite) -a <autostop cond.> ... duration:NUM - stop after NUM seconds filesize:NUM - stop this file after NUM KB files:NUM - stop after NUM files Capture output: -b <ringbuffer opt.> ... duration:NUM - switch to next file after NUM secs filesize:NUM - switch to next file after NUM KB files:NUM - ringbuffer: replace after NUM files RPCAP options: -A <user>:<password> use RPCAP password authentication Input file: -r <infile> set the filename to read from (no pipes or stdin!) Processing: -2 perform a two-pass analysis -R <read filter> packet Read filter in Wireshark display filter syntax -Y <display filter> packet displaY filter in Wireshark display filter syntax -n disable all name resolutions (def: all enabled) -N <name resolve flags> enable specific name resolution(s): "mntC" -d <layer_type>==<selector>,<decode_as_protocol> ... "Decode As", see the man page for details Example: tcp.port==8888,http -H <hosts file> read a list of entries from a hosts file, which will then be written to a capture file. (Implies -W n) Output: -w <outfile|-> write packets to a pcap-format file named "outfile" (or to the standard output for "-") -C <config profile> start with specified configuration profile -F <output file type> set the output file type, default is libpcap an empty "-F" option will list the file types -V add output of packet tree (Packet Details) -O <protocols> Only show packet details of these protocols, comma separated -P print packet summary even when writing to a file -S <separator> the line separator to print between packets -x add output of hex and ASCII dump (Packet Bytes) -T pdml|ps|psml|text|fields format of text output (def: text) -e <field> field to print if -Tfields selected (e.g. tcp.port, col.Info); this option can be repeated to print multiple fields -E<fieldsoption>=<value> set options for output when -Tfields selected: header=y|n switch headers on and off separator=/t|/s|<char> select tab, space, printable character as separator occurrence=f|l|a print first, last or all occurrences of each field aggregator=,|/s|<char> select comma, space, printable character as aggregator quote=d|s|n select double, single, no quotes for values -t ad|a|r|d|dd|e output format of time stamps (def: r: rel. to first) -u s|hms output format of seconds (def: s: seconds) -l flush standard output after each packet -q be more quiet on stdout (e.g. when using statistics) -Q only log true errors to stderr (quieter than -q) -g enable group read access on the output file(s) -W n Save extra information in the file, if supported. n = write network address resolution information -X <key>:<value> eXtension options, see the man page for details -z <statistics> various statistics, see the man page for details Miscellaneous: -h display this help and exit -v display version info and exit -o <name>:<value> ... override preference setting -K <keytab> keytab file to use for kerberos decryption -G [report] dump one of several available reports and exit default report="fields" use "-G ?" for more help