pcap_fileno(3) get the file descriptor for a live capture


#include <pcap/pcap.h>

int pcap_fileno(pcap_t *p);


If p refers to a network device that was opened for a live capture using a combination of pcap_create() and pcap_activate(), or using pcap_open_live(), pcap_fileno() returns the file descriptor from which captured packets are read.

If p refers to a ``savefile'' that was opened using functions such as pcap_open_offline() or pcap_fopen_offline(), a ``dead'' pcap_t opened using pcap_open_dead(), or a pcap_t that was created with pcap_create() but that has not yet been activated with pcap_activate(), it returns -1.