unixdev.net


Switch to SpeakEasy.net DSL

The Modular Manual Browser

Home Page
Manual: (NetBSD-6.1.5)
Page:
Section:
Apropos / Subsearch:
optional field

PCAP_STATS(3)              Library Functions Manual              PCAP_STATS(3)



NAME
       pcap_stats - get capture statistics

SYNOPSIS
       #include <&lt;pcap/pcap.h>&gt;

       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(3) 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 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(3), pcap_geterr(3)



                               7 September 2009                  PCAP_STATS(3)