History of the Berkeley Software Distribution
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.
[1] A further feature was a networking package called Berknet, developed by Eric Schmidt as part of his master's thesis work, that could connect up to twenty-six computers and provided email and file transfer.
[6] Unlike the previous releases, it required split instruction/data space, to accommodate the ever-increasing size of its utility programs.
4BSD (November 1980) offered a number of enhancements over 3BSD, notably job control in the previously released csh, delivermail (the ancestor of sendmail), "reliable" signals, and the Curses programming library.
[10] The software development that would lead from 4.1BSD to 4.2BSD was funded from sources including ARPA, Order Number 4031, Contract N00039-82-C-0235 which was in effect at least from November 15, 1981 through September 30, 1983.
Before its official release came three intermediate versions: 4.1a from April 1982[13] incorporated a modified version of BBN's preliminary TCP/IP implementation; 4.1b from June 1982 included the new Berkeley Fast File System, implemented by Marshall Kirk McKusick; and 4.1c in April 1983 was an interim release during the last few months of 4.2BSD's development.
Back at Bell Labs, 4.1cBSD became the basis of the 8th Edition of Research Unix, and a commercially supported version was available from mt Xinu.
To guide the design of 4.2BSD, Duane Adams of DARPA formed a "steering committee" consisting of Bob Fabry, Bill Joy and Sam Leffler from UCB, Alan Nemeth and Rob Gurwitz from BBN, Dennis Ritchie from Bell Labs, Keith Lantz from Stanford, Rick Rashid from Carnegie Mellon, Bert Halstead from MIT, Dan Lynch from ISI, and Gerald J. Popek of UCLA.
Apart from the Fast File System, several features from outside contributors were accepted, including disk quotas and job control.
Sun Microsystems provided testing on its Motorola 68000 machines prior to release, improving portability of the system.
It was notable as the first version released after the 1982 departure of Bill Joy to co-found Sun Microsystems; Mike Karels and Marshall Kirk McKusick took on leadership roles within the project from that point forward.
On a lighter note, it also marked the debut of BSD's daemon mascot in a drawing by John Lasseter that appeared on the cover of the printed manuals distributed by USENIX.
Nonetheless, the 4.3BSD-Tahoe port (June 1988) proved valuable, as it led to a separation of machine-dependent and machine-independent code in BSD which would improve the system's future portability.
Apart from portability, the CSRG worked on an implementation of the OSI network protocol stack, improvements to the kernel virtual memory system and (with Van Jacobson of LBL) new TCP/IP algorithms to accommodate the growth of the Internet.
This led to Networking Release 1 (Net/1), which was made available to non-licensees of AT&T code and was freely redistributable under the terms of the BSD license.
Net/2 was the basis for two separate ports of BSD to the Intel 80386 architecture: the free 386BSD by William Jolitz and the proprietary BSD/386 (later renamed BSD/OS) by Berkeley Software Design (BSDi).
A further condition of the settlement was that USL would not file further lawsuits against users and distributors of the Berkeley-owned code in the upcoming 4.4BSD release.
Marshall Kirk McKusick summarizes the lawsuit and its outcome:[20] Code copying and theft of trade secrets was alleged.
Most notable among these today are perhaps the major open source BSDs: FreeBSD, NetBSD and OpenBSD, which are all derived from 386BSD and 4.4BSD-Lite by various routes.
A number of commercial operating systems are also partly or wholly based on BSD or its descendants, including Sun's SunOS and Apple Inc.'s macOS.
