PCAP_STATS(3PCAP) PCAP_STATS(3PCAP)

NAME

pcap_stats - get capture statistics

SYNOPSIS

#include <pcap/pcap.h>

int pcap_stats(pcap_t *p, struct pcap_stat *ps);

DESCRIPTION

pcap_stats() fills in the struct pcap_stat pointed to by its second
argument. The values represent packet statistics from the start of
the run to the time of the call.

pcap_stats() is supported only on live captures, not on
``savefiles''; no statistics are stored in ``savefiles'', so no
statistics are available when reading from a ``savefile''.

A struct pcap_stat has the following members:

ps_recv
number of packets received;

ps_drop
number of packets dropped because there was no room in
the operating system's buffer when they arrived,
because packets weren't being read fast enough;

ps_ifdrop
number of packets dropped by the network interface or
its driver.

The statistics do not behave the same way on all platforms. ps_recv
might count packets whether they passed any filter set with
pcap_setfilter(3PCAP) or not, or it might count only packets that
pass the filter. It also might, or might not, count packets dropped
because there was no room in the operating system's buffer when they
arrived. ps_drop is not available on all platforms; it is zero on
platforms where it's not available. If packet filtering is done in
libpcap, rather than in the operating system, it would count packets
that don't pass the filter. Both ps_recv and ps_drop might, or might
not, count packets not yet read from the operating system and thus
not yet seen by the application. ps_ifdrop might, or might not, be
implemented; if it's zero, that might mean that no packets were
dropped by the interface, or it might mean that the statistic is
unavailable, so it should not be treated as an indication that the
interface did not drop any packets.

RETURN VALUE

pcap_stats() returns 0 on success, PCAP_ERROR_NOT_ACTIVATED if called
on a capture handle that has been created but not activated, or
PCAP_ERROR if there is another error or if p doesn't support packet
statistics. If PCAP_ERROR is returned, pcap_geterr(3PCAP) or
pcap_perror(3PCAP) may be called with p as an argument to fetch or
display the error text.

SEE ALSO

pcap(3PCAP)

5 March 2022 PCAP_STATS(3PCAP)