Comparison of BSD operating systems

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There are a number of Unix-like operating systems based on or descended from the Berkeley Software Distribution (BSD) series of Unix variant options. The three most notable descendants in current use are FreeBSD, OpenBSD, and NetBSD, which are all derived from 386BSD and 4.4BSD-Lite, by various routes. Both NetBSD and FreeBSD started life in 1993, initially derived from 386BSD, but in 1994 migrated to a 4.4BSD-Lite code base. OpenBSD was forked from NetBSD in 1995. Other notable derivatives include DragonFly BSD, which was forked from FreeBSD 4.8.

Contents

Most of the current BSD operating systems are open source and available for download, free of charge, under the BSD License. They also generally use a monolithic kernel architecture, apart from DragonFly BSD which feature hybrid kernels. The various open source BSD projects generally develop the kernel and userland programs and libraries together, the source code being managed using a single central source repository.

In the past, BSD was also used as a basis for several proprietary versions of UNIX, such as Sun's SunOS, Sequent's Dynix, NeXT's NeXTSTEP, DEC's Ultrix and OSF/1 AXP (which became the now discontinued Tru64 UNIX).

Aims and philosophies

FreeBSD

FreeBSD aims to make an operating system usable for any purpose. [1] It is intended to run a wide variety of applications, be easy to use, contain cutting edge features, and be highly scalable, including for network servers with very high loads. [2] FreeBSD is free software, and the project prefers the FreeBSD license. However, they sometimes accept non-disclosure agreements (NDAs) and include a limited number of nonfree hardware abstraction layer (HAL) modules for specific device drivers in their source tree, to support the hardware of companies who do not provide purely libre drivers (such as HALs to program software-defined radios so that vendors do not share their nonfree algorithms).

To maintain a high level of quality and provide good support for "production quality commercial off-the-shelf (COTS) workstation, server, and high-end embedded systems", FreeBSD focuses on a narrow set of architectures. [3] A significant focus of development since 2000 [4] has been fine-grained locking and symmetric multiprocessing (SMP) scalability. From 2007 on, most of the kernel was fine-locked and scaling improvements started to be seen. [5] Other recent work includes Common Criteria security functionality, such as mandatory access control and security event audit support.

Derivatives:

NetBSD

NetBSD aims to provide a freely redistributable operating system that professionals, hobbyists, and researchers can use in any manner they wish. The main focus is portability, through the use of clear distinctions between machine-dependent and machine-independent code. It runs on a wide variety of 32-bit and 64-bit processor architectures and hardware platforms, and is intended to interoperate well with other operating systems. NetBSD places emphasis on correct design, well-written code, stability, and efficiency, where practical, close compliance with open API and protocol standards is also aimed for. In June 2008, the NetBSD Foundation moved to a two-clause BSD license, citing changes at UCB and industry applicability. [10] NPF is a project spawned by NetBSD.

Derivatives:

OpenBSD

OpenBSD is a security-focused BSD known for its developers' insistence on extensive, ongoing code auditing for security and correct functionality, a "secure by default" philosophy, good documentation, and adherence to strictly open source licensing. The system incorporates numerous security features that are absent or optional in other versions of BSD. The OpenBSD policy on openness extends to hardware documentation and drivers, since without these, there can be no trust in the correct operation of the kernel and its security, and vendor software bugs would be hard to resolve. [12]

OpenBSD emphasizes very high standards in all areas. Security policies include disabling all non-essential services and having sane initial settings; and integrated cryptography (originally made easier due to relaxed Canadian export laws relative to the United States), full public disclosure of all security flaws discovered; thoroughly auditing code for bugs and security issues; various security features, including the W^X page protection technology and heavy use of randomization to mitigate attacks. Coding approaches include an emphasis on searching for similar issues throughout the code base if any code issue is identified. Concerning software freedom, OpenBSD prefers the BSD or ISC license, with the GPL acceptable only for existing software which is impractical to replace, such as the GNU Compiler Collection. NDAs are never considered acceptable. In common with its parent, NetBSD, OpenBSD strives to run on a wide variety of hardware. [13] Where licenses conflict with OpenBSD's philosophy, the OpenBSD team has re-implemented major pieces of software from scratch, which have often become the standard used within other versions of BSD. Examples include the pf packet filter, new privilege separation techniques used to safeguard tools such as tcpdump and tmux, much of the OpenSSH codebase, and replacing GPL licensed tools such as diff, grep and pkg-config with ISC or BSD licensed equivalents.

OpenBSD prominently notes the success of its security approach on its website home page. As of July 2024, only two vulnerabilities have ever been found in its default install (an OpenSSH vulnerability found in 2002, and a remote network vulnerability found in 2007) in a period of almost 22 years. According to OpenBSD expert Michael W. Lucas, OpenBSD "is widely regarded as the most secure operating system available anywhere, under any licensing terms." [14]

OpenBSD has spawned numerous child projects such as OpenSSH, OpenNTPD, OpenBGPD, OpenSMTPD, PF, CARP, and LibreSSL. Many of these are designed to replace restricted alternatives.

Derivatives:

DragonFly BSD

DragonFly BSD aims to be inherently easy to understand and develop for multi-processor infrastructures. The main goal of the project, forked from FreeBSD 4.8, is to radically change the kernel architecture, introducing microkernel-like message passing which will enhance scaling and reliability on symmetric multiprocessing (SMP) platforms while also being applicable to NUMA and clustered systems. The long-term goal is to provide a transparent single system image in clustered environments. DragonFly BSD originally supported both the IA-32 and x86-64 platforms, however support for IA-32 was dropped in version 4.0. [22] [23] Matthew Dillon, the founder of DragonFly BSD, believes supporting fewer platforms makes it easier for a project to do a proper, ground-up symmetric multiprocessing implementation. [24]

Popularity

Bar chart showing the proportion of users of each BSD variant from a BSD usage survey from September 2005. Bsd distributions usage.svg
Bar chart showing the proportion of users of each BSD variant from a BSD usage survey from September 2005.

In September 2005, the BSD Certification Group, after advertising on a number of mailing lists, surveyed 4,330 BSD users, 3,958 of whom took the survey in English, to assess the relative popularity of the various BSD operating systems. About 77% of respondents used FreeBSD, 33% used OpenBSD, 16% used NetBSD, 2.6% used Dragonfly, and 6.6% used other (potentially non-BSD) systems. Other languages offered were Brazilian and European Portuguese, German, Italian, and Polish. Note that there was no control group or pre-screening of the survey takers. Those who checked "Other" were asked to specify that operating system. [25]

Because survey takers were permitted to select more than one answer, the percentages shown in the graph, which are out of the number survey of participants, add up to greater than 100%. If a survey taker filled in more than one choice for "other", this is still only counted as one vote for other on this chart. [25]

Another attempt to profile worldwide BSD usage is the *BSDstats Project, whose primary goal is to demonstrate to hardware vendors the penetration of BSD and viability of hardware drivers for the operating system. The project collects data monthly from any BSD system administrators willing to participate, and currently records the BSD market share of participating FreeBSD, OpenBSD, NetBSD, DragonflyBSD, Debian GNU/kFreeBSD, TrueOS, and MirBSD systems. [26]

In 2020, a new independent project was introduced to collect statistics with the goal of significantly increasing the number of observed parameters. [27]

DistroWatch, well known in the Linux community and often used as a rough guide to free operating system popularity, publishes page hits for each of the Linux distributions and other operating systems it covers. As of 27 March 2020, using a data span of the last six months it placed FreeBSD in 21st place with 452 hits per day, GhostBSD in 51st place with 243 hits, TrueOS in 54th place with 182 hits per day, DragonflyBSD in 75th place with 180 hits, OpenBSD in 80th place with 169 hits per day and NetBSD in 109th place with 105 hits per day. [28]

Names, logos, slogans

The names FreeBSD and OpenBSD are references to software freedom: both in cost and open source. [29] NetBSD's name is a tribute to the Internet, which brought the original developers together. [30]

The first BSD mascot was the BSD daemon, named after a common type of Unix software program, a daemon . FreeBSD still uses the image, a red cartoon daemon named Beastie, wielding a pitchfork, as its mascot today. In 2005, after a competition, a stylized version of Beastie's head designed and drawn by Anton Gural was chosen as the FreeBSD logo. [31] The FreeBSD slogan is "The Power to Serve."

The NetBSD flag, designed in 2004 by Grant Bissett, is inspired by the original NetBSD logo, [32] designed in 1994 by Shawn Mueller, portraying a number of BSD daemons raising a flag on top of a mound of computer equipment. This was based on a World War II photograph, Raising the Flag on Iwo Jima. The Board of Directors of The NetBSD Foundation believed this was too complicated, too hard to reproduce and had negative cultural ramifications and was thus not a suitable image for NetBSD in the corporate world. The new, simpler flag design replaced this. [33] The NetBSD slogan is "Of course it runs NetBSD", referring to the operating system's portability.

Originally, OpenBSD used the BSD daemon as a mascot, sometimes with an added halo as a distinguishing mark, but OpenBSD later replaced its BSD daemon with Puffy. Although Puffy is usually referred to as a pufferfish, the spikes on the cartoon images give him a closer likeness to the porcupinefish. The logo is a reference to the fish's defensive capabilities and to the Blowfish cryptography algorithm used in OpenSSH. OpenBSD also has a number of slogans including "Secure by default", which was used in the first OpenBSD song, "E-railed", and "Free, Functional & Secure", [34] and OpenBSD has released at least one original song with every release since 3.0. [35]

The DragonFly BSD logo, designed by Joe Angrisano, is a dragonfly named Fred. [36] A number of unofficial logos [37] by various authors also show the dragonfly or stylized versions of it. DragonFly BSD considers itself to be "the logical continuation of the FreeBSD 4.x series." [38] FireflyBSD has a similar logo, a firefly, showing its close relationship to DragonFly BSD. In fact, the FireflyBSD website states that proceeds from sales will go to the development of DragonFly BSD, suggesting that the two may in fact be very closely related.

PicoBSD's slogan is "For the little BSD in all of us," and its logo includes a version of FreeBSD's Beastie as a child, [39] showing its close connection to FreeBSD, and the minimal amount of code needed to run as a Live CD.

A number of BSD OSes use stylized version of their respective names for logos. This includes TrueOS, GhostBSD, DesktopBSD, ClosedBSD, [40] and MicroBSD. [41] TrueOS's slogan is "Personal computing, served up BSD style!", GhostBSD's "A simple, secure BSD served on a Desktop." DesktopBSD's "A Step Towards BSD on the Desktop." MicroBSD's slogan is "The small secure unix like OS."

MirOS's site collects a variety of BSD mascots and Tux, the Linux mascot, together, illustrating the project's aim of supporting both BSD and Linux kernels. MirOS's slogan is "a wonderful operating system for a world of peace." [42]

General information

Overview of BSD versions
NamePrimary developersFirst public releaseBased onLatest stable versionCost (USD)Preferred license PurposeShort description
VersionRelease Date
FreeBSD The FreeBSD Project1993-12-01 386BSD, 4.4BSD-Lite142023-11-20 [43] Free Simplified BSD Server, Workstation, Network Appliance, Embedded Aims to be usable for any purpose.
OpenBSD The OpenBSD Project1996-09-01 NetBSD 1.0 7.52024-04-05 [44] Free ISC Server, Workstation, Network Appliance, Embedded Aims for maximum correctness in code, bringing simplicity and security.
NetBSD The NetBSD Project1993-04-19 386BSD, 4.4BSD-Lite10.02024-03-28 [45] Free Simplified BSD Server, Workstation, Network Appliance, Embedded Aims for maximum portability.
DragonFly BSD Matt Dillon 2004-07-12 FreeBSD 4.86.4.02022-12-30 [46] Free Modified BSD Server, Workstation, Network Appliance, Embedded Aims for maximum scalability.
386BSD [Note 1] William and Lynne Jolitz 1992-03-01 4.3BSD Net/22.02016-08-05Free BSD Open source general purposeHistorical
BSD/OS (BSD/386) [Note 1] BSDi, Wind River Systems 1993-03-01 4.3BSD Net/2, 4.4BSD 5.12003-10-01 ? Proprietary General purposeHistorical
SunOS [Note 1] [Note 2] Sun Microsystems 19824.xBSD, UNIX System V [47] 4.1.41994-11-01Included in hardware and support charges Proprietary Server, Workstation Historical (Solaris is a different code base)
Ultrix [Note 1] Digital Equipment Corporation 19844.2BSD, SVR2 4.51995 ? Proprietary General PurposeHistorical (ran on DEC VAX & MIPS systems or emulators).
RISCiX Acorn Computers 19884.3 BSD, Unix System V 1.31c1993-09-07Cost £1000 GBP (Approx $1400) Proprietary Workstation Historical (ran on Archimedes and R series Workstations)
Tru64 UNIX (DEC OSF/1, Digital UNIX) DEC, Compaq, HP 19934.3BSD, 4.4BSD, Mach 2.5, UNIX System V 5.1B-62010-10-01Cost $99 (non-commercial) Proprietary General PurposeOnly runs on HP Alpha systems or emulators.
Darwin Apple Inc. 2001-03-01 NeXTSTEP, FreeBSD, classic Mac OS 22.5.02023-05-18Free APSL, GPL and others Workstation, Home Desktop, Server The kernel and certain userland components of macOS and iOS
TrueOS iXsystems, Inc. 2006-04-29 FreeBSD 18.122018-12-15Free BSD Server Easy to use while maintaining full use of FreeBSD base
GhostBSD Eric Turgeon2009-11-01 FreeBSD 24.01.12024-02-13Free BSD Desktop, Workstation Easy to use, full FreeBSD w/ GNOME, Mate, Xfce, LXDE or Openbox.
FuryBSDJoe Maloney2019-10-24 FreeBSD
12.1-2020090701 (2020Q3)		2019-12-02Free BSD Desktop, Workstation Easy to use, full FreeBSD w/ Xfce or KDE.
DesktopBSD Peter Hofer, Daniel Seuffert2005-07-25 FreeBSD 1.72009-09-07Free BSD DesktopEasy to use
ClosedBSDJoshua Bergeron and various contributors  ? FreeBSD 1.0B (floppy), 1.0-RC1 (CD) ?Free Proprietary  ?firewall/NAT, boot floppy, Live CD
FreeSBIE  ? ? FreeBSD 2.0.32007-02-01Free ? ? Live CD of FreeBSD. DistroWatch lists as discontinued.
PicoBSD Michael Bialecki ? FreeBSD 0.42 ?Free BSD boot floppy ?
Anonym.OS  ?2005-01-01 OpenBSD 3.8none (beta only) ?Free ?Anonymous browsing Live CD
MirOS BSD The MirOS Project ? OpenBSD 3.1#102008-03-16Free ? ?European
ekkoBSD [Note 1] Rick Collette ? OpenBSD 3.3 ? ? ? ? Server easy to administer
MicroBSD [Note 1] Bulgarians ? OpenBSD 3.0/3.40.62003-10-27Free ?General purposeSmall, secure
OliveBSD Gabriel Paderni ? OpenBSD 3.8 ? ?Free ? Live CD DistroWatch lists as discontinued.
Gentoo/FreeBSD Gentoo Linux developers ? FreeBSD  ? ?Free GPL, BSDServer, Workstation, Network Applianceuses Gentoo framework
Gentoo/OpenBSD Gentoo Linux developers ? OpenBSD  ? ?FreeGPL, BSDServer, Workstation, Network Appliance, Embeddeduses Gentoo framework
Gentoo/NetBSD Gentoo Linux developers ? NetBSD  ? ?FreeGPL, BSDServer, Workstation, Network Appliance, Embeddeduses Gentoo framework
Gentoo/DragonflyBSDRobert Sebastian Gerus (project not yet officially supported by Gentoo) ? DragonFly BSD  ? ?Free ?Server, Workstation, Network Applianceuses Gentoo framework
Debian GNU/kFreeBSD The Debian GNU/kFreeBSD team2011-02-06 GNU, FreeBSD 7.52014-04-26FreeDFSGGeneral purposeGNU userspace on FreeBSD kernel
Debian GNU/NetBSD The Debian GNU/kNetBSD teamAbandoned GNU, NetBSD AbandonedAbandonedFreeDFSGGeneral purposeGNU userspace on NetBSD kernel
MidnightBSD [48] Lucas Holt2007-08-04 FreeBSD 6.1 beta [49] 3.0.12023-04-03Free BSD Desktop GNUstep based Desktop Environment
NomadBSD [50] The NomadBSD Team2018-03-25 FreeBSD 140R-202401262024-01-26 [51] Free BSD Live USB Openbox based Desktop Environment
pfSense various contributors 2006-10-04 FreeBSD 2.7.02023-06-29Free BSD Security appliancefirewall/NAT, Live CD
OPNsense various contributors 2015-01-02 pfSense 23.7.52023-09-26Free BSD Security appliancefirewall/NAT, Live CD
Paxym FreeBSD for OcteonPaxym Inc.2007-12-11 FreeBSD 7.04.72008-08-13 ? Proprietary Network, Storage, Security Applications: Routers/UTM/Firewall/NASFor Cavium Networks Octeon MIPS architecture multicore processors [52]
KarmaBSD [53]  ? FreeBSD 8
OpenBSD 		 ? ?Free Free software FreeBSD, OpenBSD Firewall, MP3 player, backup, others
Jibbed [54] OpenBSD, NetBSD 6.0Free BSD Live CD of NetBSD
Bitrig The Bitrig Developers2014-11-25 OpenBSD 1.02014-11-25Free ISC General PurposeFocus on modern platforms and tools
StarBSDdigital IXI Corp2009-12-01 FreeBSD 2020.32020-03-25Free Simplified BSD Server, Workstation, Network Appliance, Embedded Aims for maximum scalability.
DeveloperFirst public releaseBased onVersionRelease DateCost (USD)Preferred license PurposeShort description
  1. 1 2 3 4 5 6 386BSD, BSD/OS, SunOS, and Ultrix are historic operating systems that are no longer developed. BSDeviant and ekkoBSD do not exist anymore either, although BSDeviant is still available for download (see external links). MicroBSD ended, then started again in 2003, but it does not seem that any progress has been made since then, though the website still exists.
  2. ↑ This article only refers to SunOS through version 4.x. SunOS from release 5.x forward is based on SVR4, and is most commonly referred to as Solaris.

See also

Notes and references

  1. ↑ "Chapter 1 Introduction: 1.2. – What is the goal of the FreeBSD Project?". Frequently Asked Questions for FreeBSD 4.X, 5.X, and 6.X. The FreeBSD Documentation Project. 1995–2006. Retrieved 2006-04-22.
  2. ↑ "About FreeBSD". The FreeBSD Project. 2006-10-12. Retrieved 2006-10-14.
  3. ↑ "Support for Multiple Architectures: Statement of General Intent". Committer's Guide. The FreeBSD Documentation Project. Retrieved 2006-10-14. The FreeBSD Project targets "production quality commercial off-the-shelf (COTS) workstation, server, and high-end embedded systems".
  4. ↑ "Destabilization due to SMP development". Archived from the original on 3 February 2015. Retrieved 27 May 2015.
  5. ↑ Baldwin, John (February 6, 2013). "How SMPng Works and Why It Doesn't Work The Way You Think" (PDF).
  6. ↑ "FuryBSD.org capture from 1st Nov 2020". FuryBSD. Archived from the original on 2020-11-01. Retrieved 1 November 2020.
  7. ↑ "TrueOS Discontinuation". TrueOS. Retrieved 5 May 2020.
  8. ↑ "Hello — helloSystem documentation". helloSystem. Retrieved 16 October 2021.
  9. ↑ "CheriBSD". University of Cambridge. Retrieved 19 April 2022.
  10. ↑ "About the NetBSD Project – What is the NetBSD project?". The NetBSD Foundation, Inc. 2006-01-08. Retrieved 2006-04-22.
  11. ↑ "A fast, open and Secure desktop Operating System based on NetBSD". 2020-11-13. Retrieved 2021-08-02.
  12. ↑ de Raadt, Theo (5 December 2006). "Presentation at OpenCON". OpenBSD. Retrieved 13 December 2011.
  13. ↑ "OpenBSD Project Goals". OpenBSD. 2005-10-12. Retrieved 2006-04-22.
  14. ↑ Lucas, Michael W. (2013). Absolute OpenBSD: Unix for the practical paranoid (2nd ed.). San Francisco: No Starch Press. p. xxix. ISBN   978-1-59327-476-4.
  15. ↑ "Liberty BSD". libertybsd.net. Archived from the original on August 30, 2018.
  16. ↑ Andrews, Jeremy (2006-04-19). "Interview with Jonathan Gray and Damien Bergamini". kerneltrap.org. Archived from the original on 2007-12-11. Retrieved 2008-01-06.
  17. ↑ "LibertyBSD - FAQ". LibertyBSD. Retrieved 7 September 2021.
  18. ↑ Levesque, Jaidyn. "LibertyBSD". LibertyBSD. Retrieved 2021-09-07.
  19. ↑ pavroo (17 May 2021). "Isotop". ArchiveOS. Retrieved 2022-05-06.
  20. ↑ "3hg | isotop - index". www.3hg.fr. Archived from the original on 2022-04-01. Retrieved 2022-05-06.
  21. ↑ "DistroWatch.com: Put the fun back into computing. Use Linux, BSD". distrowatch.com. Retrieved 2022-05-06.
  22. ↑ "DragonFly Frequently Asked Questions". The DragonFly BSD Project. Archived from the original on 2006-06-15. Retrieved 2006-07-01.
  23. ↑ "DragonFlyBSD: FAQ-English". The DragonFly BSD Project. Retrieved 2014-12-24.
  24. ↑ Biancuzzi, Federico (2004-07-08). "Behind DragonFly BSD An Interview with the developers.". O’Reilly Media, Inc. p. 3. Archived from the original on 2012-08-06. Retrieved 2006-04-29.
  25. 1 2 3 BSD Certification site; PDF of usage survey results. Retrieved on 2012-09-16.
  26. ↑ "*BSD Usage Statistics". The *BSD Stats Project. Retrieved 2006-09-30.
  27. ↑ "BSD Hardware Trends". BSD Hardware Project. Retrieved 2020-06-03.
  28. ↑ "DistroWatch.com: Put the fun back into computing". DistroWatch.com. 2001–2011. Retrieved 2016-09-04.
  29. ↑ "Chapter 1 Introduction – Why is it called FreeBSD?". Frequently Asked Questions for FreeBSD 4.X, 5.X, and 6.X. The FreeBSD Documentation Project. 1995–2006. Retrieved 2006-06-11.
  30. ↑ "About the NetBSD Project – Why the name?". The NetBSD Foundation. 1994–2006. Retrieved 2006-12-06.
  31. ↑ FreeBSD Logo Competition Archived 2006-04-13 at the Wayback Machine . The FreeBSD Project. Competition ended 2005-06-30. Retrieved on 2006-04-22.
  32. ↑ Mueller, Shawn (1994). "Original NetBSD Logo" (JPEG). The NetBSD Foundation. Retrieved 2006-04-22. Also see NetBSD Logos.
  33. ↑ Mewburn, Luke (2004-01-14). "NetBSD logo design competition". Netbsd-advocacy mailing list. Retrieved 2006-04-22.
    Linked to from:
    "Changes and NetBSD News in 2004 – NetBSD Logo Design Contest". The NetBSD Foundation, Inc. 2004-01-13. Retrieved 2006-10-14.
    Also see:
    "The NetBSD Foundation Press Release: Announcement of New Logo – NetBSD has a new logo!". The NetBSD Foundation, Inc. 2004-10-30. Retrieved 2006-04-22.
  34. ↑ "OpenBSD 3.9 – Free, Functional & Secure" (JPEG). OpenBSD. Retrieved 2006-07-01.
  35. ↑ "OpenBSD release song lyrics". OpenBSD. 2006-04-15. Retrieved 2006-04-22.
  36. ↑ "official DragonFlyBSD artwork". Archived from the original on 2008-12-25. Retrieved 2007-02-26.
  37. ↑ "DFWiki – DragonFly Artwork". The DragonFlyBSD Project. 2006-03-28. Archived from the original on 2005-04-10. Retrieved 2006-04-22.{{cite web}}: CS1 maint: unfit URL (link)
  38. ↑ "The History of DragonFly". The DragonFly BSD Project. Archived from the original on 2006-04-14. Retrieved 2006-04-22.
  39. ↑ "PicoBSD Banner – For the little BSD in all of us". The FreeBSD Project. Archived from the original (GIF) on 2006-05-03. Retrieved 2006-04-22.
  40. ↑ "ClosedBSD logo". Archived from the original (JPEG) on 2005-03-06. Retrieved 2006-10-14. Original last retrieved on 2006-04-22.
  41. ↑ "MicroBSD logo – The small secure unix like OS". Archived from the original (PNG) on 2006-04-25. Retrieved 2006-04-22.
  42. ↑ "MirOS/MirPorts: a wonderful operating system for a world of peace". MirOS Project. Archived from the original on 2006-04-12. Retrieved 2006-04-22.
  43. ↑ "FreeBSD 14-RELEASE Announcement". The FreeBSD Project. Retrieved 2023-11-23.
  44. ↑ "OpenBSD 7.5". OpenBSD. Retrieved 17 April 2024.
  45. ↑ "Announcing NetBSD 10.0 (Mar 28, 2024)".
  46. ↑ "DragonFly BSD 6.4". Dragonfly BSD. Retrieved 2023-10-13.
  47. ↑ "SunOS 4.1.3: svidii – overview of the System V environment". FreeBSD Hypertext Man Pages. The FreeBSD Project. 1989-09-30. Retrieved 2006-06-14.
  48. ↑ "MidnightBSD News" . Retrieved 27 May 2015.
  49. ↑ "About MidnightBSD" . Retrieved 27 May 2015.
  50. ↑ "NomadBSD" . Retrieved 24 February 2024.
  51. ↑ "NomadBSD 140R-20240126 is now available!" . Retrieved 24 February 2024.
  52. ↑ "Paxym – FreeBSD for OCTEON CPU" . Retrieved 27 May 2015.
  53. ↑ "One Floppy OpenBSD MP3 Player". Archived from the original on 3 December 2013. Retrieved 27 May 2015.
  54. ↑ jibbed.org

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GNU variants are operating systems based upon the GNU operating system. According to the GNU project and others, these also include most operating systems using the Linux kernel and a few others using BSD-based kernels.

<span class="mw-page-title-main">Berkeley Software Distribution</span> Unix operating system

The Berkeley Software Distribution or Berkeley Standard Distribution (BSD) is a discontinued operating system based on Research Unix, developed and distributed by the Computer Systems Research Group (CSRG) at the University of California, Berkeley. Since the original has become obsolete, the term "BSD" is commonly used for its open-source descendants, including FreeBSD, OpenBSD, NetBSD, and DragonFly BSD.

<span class="mw-page-title-main">OpenBSD</span> Operating system

OpenBSD is a security-focused, free software, Unix-like operating system based on the Berkeley Software Distribution (BSD). Theo de Raadt created OpenBSD in 1995 by forking NetBSD 1.0. The OpenBSD project emphasizes portability, standardization, correctness, proactive security, and integrated cryptography.

<span class="mw-page-title-main">NetBSD</span> Free and open-source Unix-like operating system

NetBSD is a free and open-source Unix-like operating system based on the Berkeley Software Distribution (BSD). It was the first open-source BSD descendant officially released after 386BSD was forked. It continues to be actively developed and is available for many platforms, including servers, desktops, handheld devices, and embedded systems.

<span class="mw-page-title-main">Lumina (desktop environment)</span> Desktop environment for X Window System

Lumina Desktop Environment, or simply Lumina, is a plugin-based desktop environment for Unix and Unix-like operating systems. It was designed specifically as a system interface for TrueOS and systems derived from Berkeley Software Distribution (BSD) in general, but it has been ported to various Linux distributions.

The history of the Berkeley Software Distribution began in the 1970s when University of California, Berkeley received a copy of Unix. Professors and students at the university began adding software to the operating system and released it as BSD to select universities. Since it contained proprietary Unix code, it originally had to be distributed subject to AT&T licenses. The bundled software from AT&T was then rewritten and released as free software under the BSD license. However, this resulted in a lawsuit with Unix System Laboratories, the AT&T subsidiary responsible for Unix. Eventually, in the 1990s, the final versions of BSD were publicly released without any proprietary licenses, which led to many descendants of the operating system that are still maintained today.

A virtual kernel architecture (vkernel) is an operating system virtualisation paradigm where kernel code can be compiled to run in the user space, for example, to ease debugging of various kernel-level components, in addition to general-purpose virtualisation and compartmentalisation of system resources. It is used by DragonFly BSD in its vkernel implementation since DragonFly 1.7, having been first revealed in September 2006, and first released in the stable branch with DragonFly 1.8 in January 2007.

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