Manpages - pcap_lookupdev.3pcap

pcap_lookupdev - find the default device on which to capture

  #include <pcap/pcap.h>
  char errbuf[PCAP_ERRBUF_SIZE];
  [DEPRECATED] char *pcap_lookupdev(char *errbuf);

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.)

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. errbuf is assumed to be able to hold at least PCAP_ERRBUF_SIZE chars.

*pcap*(3PCAP)

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.