If p refers to a network device that was opened for a live capture
using a combination of pcap_create() and pcap_activate(), or using
pcap_open_live(), pcap_fileno() returns the file descriptor from
which captured packets are read.
If p refers to a ``savefile'' that was opened using functions such as
pcap_open_offline() or pcap_fopen_offline(), a ``dead'' pcap_t opened
using pcap_open_dead(), or a pcap_t that was created with
pcap_create() but that has not yet been activated with
pcap_activate(), it returns -1.
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 2017-04-25. 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 email@example.com
7 April 2014 PCAP_FILENO(3PCAP)