tcpdump

To report bugs and other problems, contribute patches, request a feature, provide generic feedback etc please see the guidelines for contributing in the tcpdump source tree root. This directory contains source code for tcpdump, a tool for network monitoring and data acquisition. Over the past few years, tcpdump has been steadily improved by the excellent contributions from the Internet community (just browse through the change log). We are grateful for all the input. Supported platforms In many operating systems tcpdump is available as a native package or port, which simplifies installation of updates and long-term maintenance. However, the native packages are sometimes a few versions behind and to try a more recent snapshot it will take to compile tcpdump from the source code. 4.3BSD BSD/386, later BSD/OS DEC OSF/1, later Digital UNIX, later Tru64 UNIX DOS IRIX LynxOS SINIX SunOS Ultrix UnixWare Dependency on libpcap tcpdump uses libpcap, a system-independent interface for user-level packet capture. If your operating system does not provide libpcap, or if it provides a libpcap that does not support the APIs from libpcap 1.0 or later, you must first retrieve and build libpcap before building tcpdump, Once libpcap is built (either install it or make sure it's in ../libpcap ), you can build tcpdump using the procedure in the installation notes. See also Richard Stevens gives an excellent treatment of the Internet protocols in his book "TCP/IP Illustrated, Volume 1" . If you want to learn more about tcpdump and how to interpret its output, pick up this book.