1PCAP_STATS(3PCAP) PCAP_STATS(3PCAP)
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6 pcap_stats - get capture statistics
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9 #include <pcap/pcap.h>
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11 int pcap_stats(pcap_t *p, struct pcap_stat *ps);
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14 pcap_stats() fills in the struct pcap_stat pointed to by its second
15 argument. The values represent packet statistics from the start of the
16 run to the time of the call.
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18 pcap_stats() is supported only on live captures, not on ``savefiles'';
19 no statistics are stored in ``savefiles'', so no statistics are avail‐
20 able when reading from a ``savefile''.
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22 A struct pcap_stat has the following members:
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24 ps_recv
25 number of packets received;
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27 ps_drop
28 number of packets dropped because there was no room in
29 the operating system's buffer when they arrived, because
30 packets weren't being read fast enough;
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32 ps_ifdrop
33 number of packets dropped by the network interface or its
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36 The statistics do not behave the same way on all platforms. ps_recv
37 might count packets whether they passed any filter set with pcap_set‐
38 filter(3PCAP) or not, or it might count only packets that pass the fil‐
39 ter. It also might, or might not, count packets dropped because there
40 was no room in the operating system's buffer when they arrived.
41 ps_drop is not available on all platforms; it is zero on platforms
42 where it's not available. If packet filtering is done in libpcap,
43 rather than in the operating system, it would count packets that don't
44 pass the filter. Both ps_recv and ps_drop might, or might not, count
45 packets not yet read from the operating system and thus not yet seen by
46 the application. ps_ifdrop might, or might not, be implemented; if
47 it's zero, that might mean that no packets were dropped by the inter‐
48 face, or it might mean that the statistic is unavailable, so it should
49 not be treated as an indication that the interface did not drop any
50 packets.
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53 pcap_stats() returns 0 on success and returns -1 if there is an error
54 or if p doesn't support packet statistics. If -1 is returned,
55 pcap_geterr() or pcap_perror() may be called with p as an argument to
56 fetch or display the error text.
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59 pcap(3PCAP), pcap_geterr(3PCAP)
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63 3 January 2014 PCAP_STATS(3PCAP)