Merge libpcap-1.1.1.

1 files changed, 45 insertions, 5 deletions

diff --git a/contrib/libpcap/pcap_stats.3pcap b/contrib/libpcap/pcap_stats.3pcap
index 0a68c1e..a953e21 100644
--- a/contrib/libpcap/pcap_stats.3pcap
+++ b/contrib/libpcap/pcap_stats.3pcap
@@ -1,4 +1,4 @@
-.\" @(#) $Header: /tcpdump/master/libpcap/pcap_stats.3pcap,v 1.1.2.3 2008-04-06 03:21:56 guy Exp $
+.\" @(#) $Header: /tcpdump/master/libpcap/pcap_stats.3pcap,v 1.3 2008-04-06 02:53:22 guy Exp $
 .\"
 .\" Copyright (c) 1994, 1996, 1997
 .\"	The Regents of the University of California.  All rights reserved.
@@ -19,7 +19,7 @@
 .\" WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 .\" MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 .\"
-.TH PCAP_SNAPSHOT 3PCAP "5 April 2008"
+.TH PCAP_STATS 3PCAP "7 September 2009"
 .SH NAME
 pcap_stats \- get capture statistics
 .SH SYNOPSIS
@@ -35,17 +35,57 @@ int pcap_stats(pcap_t *p, struct pcap_stat *ps);
 .SH DESCRIPTION
 .B pcap_stats()
 fills in the
-.I pcap_stat
-structure pointed to by its second argument.  The values represent
+.B 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.
 .PP
 .B 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''.
+.PP
+A
+.B struct pcap_stat
+has the following members:
+.RS
+.TP
+.B ps_recv
+number of packets received;
+.TP
+.B 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;
+.TP
+.B ps_ifdrop
+number of packets dropped by the network interface or its driver.
+.RE
+.PP
+The statistics do not behave the same way on all platforms.
+.B ps_recv
+might count packets whether they passed any filter set with
+.BR 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.
+.B 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
+.B ps_recv
+and
+.B ps_drop
+might, or might not, count packets not yet read from the operating
+system and thus not yet seen by the application.
+.B 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.
 .SH RETURN VALUE
 .B pcap_stats()
-returns 0 on success and returns \-1 if there is an error or the
+returns 0 on success and returns \-1 if there is an error or if
 .I p
 doesn't support packet statistics.
 If \-1 is returned,