PCAP_OPEN_LIVE
Section: Misc. Reference Manual Pages (3PCAP)
Updated: 6 December 2017
Page Index
NAME
pcap_open_live - open a device for capturing
SYNOPSIS
#include <pcap/pcap.h>
char errbuf[PCAP_ERRBUF_SIZE];
pcap_t *pcap_open_live(const char *device, int snaplen,
int promisc, int to_ms, char *errbuf);
DESCRIPTION
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 if the interface is to be put into promiscuous mode.
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.)
RETURN VALUE
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.
SEE ALSO
pcap(3PCAP),
pcap_create(3PCAP),
pcap_activate(3PCAP)