PCAP_OPEN_LIVE(3PCAP) PCAP_OPEN_LIVE(3PCAP) NAME pcap_open_live - open a device for capturing SYNOPSIS #include <pcap/pcap.h> char errbuf[PCAP_ERRBUF_SIZE]; pcap_t *pcap_open_live(const char *device, int snaplen, int promisc, int to_ms, char *errbuf); DESCRIPTION pcap_open_live() is used to obtain a packet capture handle to look at pack- ets on the network. device is a string that specifies the network device to open; on all supported Linux systems, as well as on recent versions of macOS and Solaris, a device argument of "any" or NULL can be used to cap- ture packets from all network interfaces. The latter should not be con- fused with all available capture devices as seen by pcap_find- alldevs(3PCAP), which may also include D-Bus, USB etc. snaplen specifies the snapshot length to be set on the handle. If the packet data should not be truncated at the end, a value of 262144 should be sufficient for most devices, but D-Bus devices require a value of 128MB (128*1024*1024). promisc specifies whether the interface is to be put into promiscuous mode. If promisc is non-zero, promiscuous mode will be set, otherwise it will not be set. to_ms specifies the packet buffer timeout, as a non-negative value, in mil- liseconds. (See pcap(3PCAP) for an explanation of the packet buffer time- out.) errbuf is a buffer large enough to hold at least PCAP_ERRBUF_SIZE chars. RETURN VALUE pcap_open_live() returns a pcap_t * on success and NULL on failure. If NULL is returned, errbuf is filled in with an appropriate error message. errbuf may also be set to warning text when pcap_open_live() succeeds; to detect this case the caller should store a zero-length string in errbuf be- fore calling pcap_open_live() and display the warning to the user if errbuf is no longer a zero-length string. SEE ALSO pcap_create(3PCAP), pcap_activate(3PCAP) 4 March 2024 PCAP_OPEN_LIVE(3PCAP)
NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | SEE ALSO
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