PCAP_LOOKUPDEV(3PCAP) PCAP_LOOKUPDEV(3PCAP)

NAME

pcap_lookupdev - find the default device on which to capture

SYNOPSIS

#include <pcap/pcap.h>

char errbuf[PCAP_ERRBUF_SIZE];

[DEPRECATED] char *pcap_lookupdev(char *errbuf);

DESCRIPTION

This interface is obsoleted by pcap_findalldevs(3PCAP). To find a
default device on which to capture, call pcap_findalldevs() and, if
the list it returns is not empty, use the first device in the list.
(If the list is empty, there are no devices on which capture is
possible.) errbuf is a buffer large enough to hold at least
PCAP_ERRBUF_SIZE chars.

If pcap_init(3PCAP) has been called, this interface always returns
NULL.

pcap_lookupdev() returns a pointer to a string giving the name of a
network device suitable for use with pcap_create(3PCAP) and
pcap_activate(3PCAP), or with pcap_open_live(3PCAP), and with
pcap_lookupnet(3PCAP). If there is an error, or if pcap_init(3PCAP)
has been called, NULL is returned and errbuf is filled in with an
appropriate error message.

SEE ALSO

pcap(3PCAP)

BUGS

The pointer returned by pcap_lookupdev() points to a static buffer;
subsequent calls to pcap_lookupdev() in the same thread, or calls to
pcap_lookupdev() in another thread, may overwrite that buffer.

In WinPcap and Npcap, this function may return a UTF-16 string rather
than an ASCII or UTF-8 string.

30 November 2023 PCAP_LOOKUPDEV(3PCAP)