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+To report a security issue please send an e-mail to security@tcpdump.org.
+
+To report bugs and other problems, contribute patches, request a
+feature, provide generic feedback etc please see the file
+[CONTRIBUTING](CONTRIBUTING.md) in the libpcap source tree root.
+
+The directory doc/ has README files about specific operating systems and
+options.
+
+LIBPCAP 1.x.y
+Now maintained by "The Tcpdump Group"
+https://www.tcpdump.org
+
+Anonymous Git is available via:
+        https://github.com/the-tcpdump-group/libpcap.git
+
+formerly from 	Lawrence Berkeley National Laboratory
+		Network Research Group <libpcap@ee.lbl.gov>
+		ftp://ftp.ee.lbl.gov/old/libpcap-0.4a7.tar.Z
+
+This directory contains source code for libpcap, a system-independent
+interface for user-level packet capture.  libpcap provides a portable
+framework for low-level network monitoring.  Applications include
+network statistics collection, security monitoring, network debugging,
+etc.  Since almost every system vendor provides a different interface
+for packet capture, and since we've developed several tools that
+require this functionality, we've created this system-independent API
+to ease in porting and to alleviate the need for several
+system-dependent packet capture modules in each application.
+
+For some platforms there are README.{system} files that discuss issues
+with the OS's interface for packet capture on those platforms, such as
+how to enable support for that interface in the OS, if it's not built in
+by default.
+
+The libpcap interface supports a filtering mechanism based on the
+architecture in the BSD packet filter.  BPF is described in the 1993
+Winter Usenix paper ``The BSD Packet Filter: A New Architecture for
+User-level Packet Capture''.  A compressed PostScript version can be
+found at
+
+	ftp://ftp.ee.lbl.gov/papers/bpf-usenix93.ps.Z
+
+or
+
+	https://www.tcpdump.org/papers/bpf-usenix93.ps.Z
+
+and a gzipped version can be found at
+
+	https://www.tcpdump.org/papers/bpf-usenix93.ps.gz
+
+A PDF version can be found at
+
+	https://www.tcpdump.org/papers/bpf-usenix93.pdf
+
+Although most packet capture interfaces support in-kernel filtering,
+libpcap utilizes in-kernel filtering only for the BPF interface.
+On systems that don't have BPF, all packets are read into user-space
+and the BPF filters are evaluated in the libpcap library, incurring
+added overhead (especially, for selective filters).  Ideally, libpcap
+would translate BPF filters into a filter program that is compatible
+with the underlying kernel subsystem, but this is not yet implemented.
+
+BPF is standard in 4.4BSD, BSD/OS, NetBSD, FreeBSD, OpenBSD, DragonFly
+BSD, and macOS; an older, modified and undocumented version is standard
+in AIX.  {DEC OSF/1, Digital UNIX, Tru64 UNIX} uses the packetfilter
+interface but has been extended to accept BPF filters (which libpcap
+utilizes).  Also, you can add BPF filter support to Ultrix using the
+kernel source and/or object patches available in:
+
+	https://www.tcpdump.org/other/bpfext42.tar.Z
+
+Linux has a number of BPF based systems, and libpcap does not support
+any of the eBPF mechanisms as yet, although it supports many of the
+memory mapped receive mechanisms.
+See the [README.linux](doc/README.linux.md) file for more information.
+
+Note to Linux distributions and *BSD systems that include libpcap:
+
+There's now a rule to make a shared library, which should work on Linux
+and *BSD, among other platforms.
+
+It sets the soname of the library to "libpcap.so.1"; this is what it
+should be, *NOT* libpcap.so.1.x or libpcap.so.1.x.y or something such as
+that.
+
+We've been maintaining binary compatibility between libpcap releases for
+quite a while; there's no reason to tie a binary linked with libpcap to
+a particular release of libpcap.
+
+Current versions can be found at https://www.tcpdump.org.
+
+ - The TCPdump group