PCAP_DATALINK(3PCAP)                                    PCAP_DATALINK(3PCAP)

NAME         top

       pcap_datalink - get the link-layer header type

SYNOPSIS         top

       #include <pcap/pcap.h>

       int pcap_datalink(pcap_t *p);

DESCRIPTION         top

       pcap_datalink() returns the link-layer header type for the live
       capture or ``savefile'' specified by p.

       It must not be called on a pcap descriptor created by pcap_create()
       that has not yet been activated by pcap_activate().  lists the values
       pcap_datalink() can return and describes the packet formats that
       correspond to those values.

       Do NOT assume that the packets for a given capture or ``savefile``
       will have any given link-layer header type, such as DLT_EN10MB for
       Ethernet.  For example, the "any" device on Linux will have a link-
       layer header type of DLT_LINUX_SLL even if all devices on the system
       at the time the "any" device is opened have some other data link
       type, such as DLT_EN10MB for Ethernet.

RETURN VALUE         top

       pcap_datalink() returns the link-layer header type on success and
       PCAP_ERROR_NOT_ACTIVATED if called on a capture handle that has been
       created but not activated.

SEE ALSO         top

       pcap(3PCAP), pcap-linktype(7)

COLOPHON         top

       This page is part of the libpcap (packet capture library) project.
       Information about the project can be found at 
       ⟨⟩.  If you have a bug report for this manual
       page, see ⟨⟩.  This page was obtained
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       ⟨⟩ on 2018-02-02.
       (At that time, the date of the most recent commit that was found in
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                                7 April 2014            PCAP_DATALINK(3PCAP)