tcap: Tcl pcap interface homepage: http://monkey.org/~jose/software/tcap/ 1. install edit the makefile for your local paths, then run "make install" as root or via sudo 2. use: $ tclsh % package require tcap % tcap help 3. more? see test.tcl for some info on how to use tcap a minimal sniffer in Tcl using tcap: #!/usr/bin/env tclsh package require tcap tcap open fxp0 0 1500 set dl [tcap dloff] tcap filter "tcp" while {1} { set g [tcap get] if {[llength [split $g]] > 0} { puts [lrange $g $dl end] } } Tcap was built and tested on BSD UNIX, should work on Linux, and has a few problems on OS X. Testing on Windows is incomplete.