PCAP_LOOKUPNET(3)      FreeBSD Library Functions Manual      PCAP_LOOKUPNET(3)

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(3) 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(3)

                                 13 March 2024               PCAP_LOOKUPNET(3)