DOKK / manpages / debian 11 / libpcap0.8-dev / pcap_lookupnet.3pcap.en
PCAP_LOOKUPNET(3PCAP) PCAP_LOOKUPNET(3PCAP)

pcap_lookupnet - find the IPv4 network number and netmask for a device

#include <pcap/pcap.h>

char errbuf[PCAP_ERRBUF_SIZE];
int pcap_lookupnet(const char *device, bpf_u_int32 *netp,
bpf_u_int32 *maskp, char *errbuf);

pcap_lookupnet() is used to determine the IPv4 network number and mask associated with the network device device. Both netp and maskp are bpf_u_int32 pointers.

pcap_lookupnet() returns 0 on success and PCAP_ERROR on failure. If PCAP_ERROR is returned, 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)

25 July 2018