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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  operat-ing operating
       ing  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 oper-ating operating
       ating  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 applica-tion. application.
       tion.   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 and returns -1 if there is an error or if p doesn't support packet
       statistics.  If -1 is returned, pcap_geterr() or pcap_perror() may be called with p as an argument to
       fetch or display the error text.

SEE ALSO
       pcap(3PCAP), pcap_geterr(3PCAP)



                                              7 September 2009                             PCAP_STATS(3PCAP)