PCAP-LINKTYPE(5) File Formats and Configurations PCAP-LINKTYPE(5)

NAME

pcap-linktype - link-layer header types supported by libpcap

DESCRIPTION

For a live capture or ``savefile'', libpcap supplies, as the return
value of the pcap_datalink(3PCAP) routine, a value that indicates the
type of link-layer header at the beginning of the packets it
provides. This is not necessarily the type of link-layer header that
the packets being captured have on the network from which they're
being captured; for example, packets from an IEEE 802.11 network
might be provided by libpcap with Ethernet headers that the network
adapter or the network adapter driver generates from the 802.11
headers. The names for those values begin with DLT_, so they are
sometimes called "DLT_ values".

The values stored in the link-layer header type field in the savefile
header are, in most but not all cases, the same as the values
returned by pcap_datalink(). The names for those values begin with
LINKTYPE_.

The link-layer header types supported by libpcap are described at
https://www.tcpdump.org/linktypes.html .

SEE ALSO

pcap(3PCAP)

6 April 2020 PCAP-LINKTYPE(5)