libpcapbased

libpcapbased is a descriptor for software whose network packet capture capabilities are implemented using the libpcap library. It denotes applications that rely on the libpcap API to access capture devices, apply filters, and process captured packets in real time or from offline pcap files. As a portable capture backend, libpcapbased programs aim to run on multiple operating systems with minimal source changes.

Core concepts and API usage include opening a capture source, applying Berkeley Packet Filter (BPF) expressions, and iterating over captured packets. Typical APIs include functions to open devices (such as pcap_open_live), compile and set filters (pcap_compile, pcap_setfilter), and retrieve packets either through a callback mechanism (pcap_loop) or a polling approach (pcap_next_ex). libpcap also supports offline processing of previously saved captures and provides error reporting and configuration options for buffer sizes and timeouts. The library emphasizes a consistent, cross‑platform interface across Unix-like systems and Windows via compatibility layers.

Common examples of libpcapbased software include network analysis and monitoring tools such as tcpdump and Wireshark, along with a wide range of intrusion detection systems, traffic analyzers, and research utilities. Developers benefit from libpcap’s abstraction over underlying capture mechanisms, enabling support for diverse interfaces and drivers without broad code changes.

Windows compatibility has evolved from WinPcap to Npcap, with Npcap providing a libpcap‑compatible API and improved driver support. This allows libpcapbased applications to function on Windows with minimal porting, alongside native Unix-like support.

Libpcap originated as part of the tcpdump project and is BSD‑licensed. It remains a foundational tool for packet capture, traffic analysis, and network research.