https://cybertoolchain.io/tools/lsof New releases and features in lsof, tracked by The Cyber Toolchain. en Tue, 16 Jun 2026 13:08:45 GMT https://github.com/lsof-org/lsof/releases/tag/4.99.7 https://github.com/lsof-org/lsof/releases/tag/4.99.7 Tue, 16 Jun 2026 13:08:45 GMT lsof 4.99.7 adds JSON and JSON Lines output formats and displays UDP connection state via -T. • Adds `-J` flag for JSON output wrapping process and file information in a structured envelope. • Adds `-j` flag for JSON Lines output where each line is a JSON object representing a file descriptor. • Enables UDP socket connection-state display on Linux via the existing `-T` option. Full history on Cyber Toolchain: https://cybertoolchain.io/tools/lsof https://github.com/lsof-org/lsof/releases/tag/4.99.7 https://github.com/lsof-org/lsof/releases/tag/4.99.7 Tue, 16 Jun 2026 13:08:45 GMT lsof 4.99.7 adds JSON and JSON Lines output formats and Linux UDP connection-state display. • Adds `-J` flag for structured JSON output, wrapping process and file descriptor information in a JSON envelope. • Adds `-j` flag for JSON Lines output, emitting one JSON object per file descriptor — ideal for streaming pipelines. • Enables UDP socket connection-state display on Linux via the existing `-T` option. Full history on Cyber Toolchain: https://cybertoolchain.io/tools/lsof https://github.com/lsof-org/lsof/releases/tag/4.99.6 https://github.com/lsof-org/lsof/releases/tag/4.99.6 Wed, 04 Mar 2026 07:12:49 GMT lsof 4.99.6 adds NETPOLICY FD parsing on Darwin, NFS ESTALE unlinked-file selection on Linux, and AIX filename capture. • Adds parsing and printing of NETPOLICY file descriptor type on Darwin. • Treats NFS ESTALE file descriptors as unlinked on Linux, enabling them to be selected with the `+L` flag. • Adds AIX platform-specific process_file() implementation with filename capture. • File name is now properly saved in liblsof on Darwin. Full history on Cyber Toolchain: https://cybertoolchain.io/tools/lsof https://github.com/lsof-org/lsof/blob/master/00DIST https://github.com/lsof-org/lsof/blob/master/00DIST Sat, 16 Dec 2023 00:00:00 GMT lsof 4.99.1 adds --disable-liblsof configure option to omit liblsof installation. • Adds `--disable-liblsof` configure option to disable installation of liblsof. Full history on Cyber Toolchain: https://cybertoolchain.io/tools/lsof https://github.com/lsof-org/lsof/releases/tag/4.99.0 https://github.com/lsof-org/lsof/releases/tag/4.99.0 Fri, 10 Nov 2023 07:12:59 GMT First alpha release of liblsof for C library access, plus OpenBSD platform support • Introduces an alpha version of `liblsof`, allowing users to access lsof functionality via C functions instead of spawning a subprocess and parsing output. • Adds a new folder separating the OpenBSD dialect to support platforms that disallow kernel memory access, requiring a switch to user mode API. Breaking changes: • On macOS, the `/dev/kmem` backend is removed and replaced with `libproc`, which may affect older macOS compatibility. Full history on Cyber Toolchain: https://cybertoolchain.io/tools/lsof https://github.com/lsof-org/lsof/blob/master/00DIST https://github.com/lsof-org/lsof/blob/master/00DIST Sun, 22 Jan 2023 00:00:00 GMT lsof 4.98.0 adds human-readable size display and root-only file listing security options • Adds `-H` switch to print file sizes in human-readable format (e.g., 123.4K) • Adds `--enable-security` configure option to restrict listing all open files to the root user only • Adds `--enable-no-sock-security` configure option to allow listing socket files even when `--enable-security` is active Full history on Cyber Toolchain: https://cybertoolchain.io/tools/lsof https://github.com/lsof-org/lsof/releases/tag/4.97.0 https://github.com/lsof-org/lsof/releases/tag/4.97.0 Tue, 17 Jan 2023 06:43:47 GMT Adds an experimental Autotools-based build system for lsof • Adds `experimental build system based on Autotools` for building lsof (#270) Breaking changes: • Removes support for the decof/du/tru64 operating systems • Removes support for the openstep/nextstep operating systems Full history on Cyber Toolchain: https://cybertoolchain.io/tools/lsof https://github.com/lsof-org/lsof/releases/tag/4.95.0 https://github.com/lsof-org/lsof/releases/tag/4.95.0 Wed, 27 Apr 2022 22:55:57 GMT Adds `-Q` option to control exit status and improves startup performance on Linux via close_range(2). • Adds the `-Q` command-line flag to adjust `lsof`'s exit status when no search items are found, allowing it to return 0 instead of the default 1. • Uses the Linux close_range(2) syscall instead of repeated close() calls during startup, significantly reducing initialization time on kernels 5.9+. Full history on Cyber Toolchain: https://cybertoolchain.io/tools/lsof