xref: /freebsd/contrib/libpcap/pcap_lookupdev.3pcap (revision cddbc3b40812213ff00041f79174cac0be360a2a)
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PCAP_LOOKUPDEV 3PCAP "3 January 2014"
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.)

pcap_lookupdev() returns a pointer to a string giving the name of a network device suitable for use with pcap_create() and pcap_activate() , or with pcap_open_live() , and with pcap_lookupnet() . If there is an error, NULL is returned and errbuf is filled in with an appropriate error message. errbuf is assumed to be able to hold at least PCAP_ERRBUF_SIZE chars.

SEE ALSO
pcap(3PCAP), pcap_create(3PCAP), pcap_activate(3PCAP), pcap_open_live(3PCAP), pcap_lookupnet(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, this function may return a UTF-16 string rather than an ASCII or UTF-8 string.