pcap_lookupnet returns incorrect IP address

Question

Following example code from the libpcap documentation yields the following code which should report the IP address of the given interface (eth0 in this case) [Error checking omi

Answer 1

Your statement "which should report the IP address of the given interface" is incorrect.

From the manpage:

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.

are you sure you have a network number of 10.0.0.107 or 192.168.1.100 respectively? Sounds rather unusual.