Copyright (c) 1994, 1996, 1997
The Regents of the University of California. All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that: (1) source code distributions
retain the above copyright notice and this paragraph in its entirety, (2)
distributions including binary code include the above copyright notice and
this paragraph in its entirety in the documentation or other materials
provided with the distribution, and (3) all advertising materials mentioning
features or use of this software display the following acknowledgement:
``This product includes software developed by the University of California,
Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
the University nor the names of its contributors may be used to endorse
or promote products derived from this software without specific prior
written permission.
THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.

PCAP_OPEN_LIVE 3PCAP "3 January 2014"
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 read timeout in milliseconds.

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)