NAME

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

SYNOPSIS

       #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);

DESCRIPTION

       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.  errbuf is a buffer large enough to hold at least
       PCAP_ERRBUF_SIZE chars.

       This function is not available on Windows.  It supports neither IPv6  nor  multiple  IPv4  addresses  per
       interface,  which  obviously is not practical in modern networks.  See pcap_findalldevs(3PCAP) for a more
       elaborate solution to the problem.

RETURN VALUE

       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.

SEE ALSO

       pcap(3PCAP)

                                                  13 March 2024                            PCAP_LOOKUPNET(3PCAP)