pcap_open_live() is used to obtain a packet capture handle to
look at packets on the network. device is a string that
specifies the network device to open; on Linux systems with 2.2
or later kernels, a device argument of "any" or NULL can be used
to capture packets from all interfaces.
snaplen specifies the snapshot length to be set on the handle.
promisc specifies whether the interface is to be put into
promiscuous mode. If promisc is non-zero, promiscuous mode will
be set, otherwise it will not be set.
to_ms specifies the packet buffer timeout, as a non-negative
value, in milliseconds. (See pcap(3PCAP) for an explanation of
the packet buffer timeout.)
pcap_open_live() returns a pcap_t * on success and NULL on
failure. If NULL is returned, errbuf is filled in with an
appropriate error message. errbuf may also be set to warning
text when pcap_open_live() succeeds; to detect this case the
caller should store a zero-length string in errbuf before calling
pcap_open_live() and display the warning to the user if errbuf is
no longer a zero-length string. errbuf is assumed to be able to
hold at least PCAP_ERRBUF_SIZE chars.
This page is part of the libpcap (packet capture library)
project. Information about the project can be found at
⟨http://www.tcpdump.org/⟩. If you have a bug report for this
manual page, see ⟨http://www.tcpdump.org/#patches⟩. This page
was obtained from the project's upstream Git repository
⟨https://github.com/the-tcpdump-group/libpcap.git⟩ on 2021-04-01.
(At that time, the date of the most recent commit that was found
in the repository was 2021-03-31.) If you discover any rendering
problems in this HTML version of the page, or you believe there
is a better or more up-to-date source for the page, or you have
corrections or improvements to the information in this COLOPHON
(which is not part of the original manual page), send a mail to
6 December 2017 PCAP_OPEN_LIVE(3PCAP)