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libpcap file format (.pcap)

The libpcap file format is used by a wide range of open (and closed) source programs.


The current libpcap file format version 2.4 is available for quite a long time now.

Programs supporting this file type


The common timestamp resolution is 1 ┬Ás. A special libpcap format is available (supported by Wireshark only), providing 1 ns timestamp resolution.


The libpcap support is fully functional. Wireshark supports reading and writing of this format.

Wireshark handles all capture file I/O in the wiretap library. You'll find further details about the libpcap file format in the source code files wiretap/libpcap.c and .h :-)

Example capture file

XXX - Add a simple example capture file to the SampleCaptures page and link from here (see below). Keep this file short, it's also a good idea to gzip it to make it even smaller, as Wireshark can open gzipped files automatically.


FileFormatReference/libpcap (last edited 2008-05-26 15:15:21 by JaapKeuter)