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[ Operating Systems ]  
  • UNIX: (by Ken Thompson and Dennis Ritchie at AT&T Bell Labs: picture (1972), former MULTICS programmers, history (D. Ritchie, 1979), history, tree, strongly interconnected with C, The Unix Heritage Society)
    Motif, OSF/1, UNIX and the "X" device are registered trademarks and IT DialTone and The Open Group are trademarks of The Open Group in the US and other countries.

  • ancient AT&T UNIX (see SCO site for source code license: application for the PDP UNIX archive access, downloads and info, history):

    3 groups at AT&T Bell Labs involved:

    system development by the "Computer Research Group" (CRG),
    "Unix System Group" (USG) responsible for support,
    "Programmer's WorkBench" (PWB) developer group,
    these groups were merged into "Unix System Development Lab" (USDL) in 1983

    first experimental version of UNIX on a PDP-7,
    1st Edition UNIX ("V1", for PDP-11, 16-Bit, 1971),
    2nd Edition UNIX ("V2"),
    3rd Edition UNIX ("V3"),
    4th Edition UNIX ("V4", 1973, first implementation in C),
    5th Edition UNIX ("V5"),
    6th Edition UNIX ("V6" or "Research UNIX", for PDP-11, 1975, BSD derived from this version),
    Mini UNIX (cut-down version of V6),
    7th Edition UNIX ("V7", for PDP-11, 1979, incl. pcc and sh),
    32/V (V7 port to VAX, 32-Bit but w/o VM, influence on 3BSD)

    then two branches: AT&T UNIX and BSD

    System III, (there has been no System IV release),
    System V,
    System V Release 2 (SVR2),
    System V Release 3 (SVR3),
    System V Release 4 (SVR4) (enhancements from BSD and SunOS (Sun´s partnership with AT&T), filesystem),
    UnixWare (SVR4 by Novell, later SCO)

    companies and history:
    System V later
    owned by "Unix System Laboratories" (USL, majority-owned by AT&T),
    AT&T sold USL (UNIX name and System V) to Novell in 1993,
    later Novell delivered control of UNIX name to X/Open (since 1996 The Open Group),
    Novell sold System V and UnixWare rights to SCO,
    SCO sold it to Caldera in 2000

  • XENIX (by SCO & Microsoft, based on AT&T System III, for Intel 286/386 platform),
    SCO UNIX (portable SCO successor of XENIX),
    SCO UnixWare (SCO UNIX successor, based on SVR4)

  • BSD: (Berkeley Software Distribution, history, twenty years of Berkeley UNIX, timeline, tree, xBSD CDROM archive and source code license from SCO)
    BSD (first distribution, for PDP-11, based on V6 + additional software),
    2BSD (for PDP-11, rework of V6)
    3BSD (for VAX, 32-Bit with VM, based on 2BSD and 32/V),
    4BSD, 4.1BSD (tuned-up 4BSD) 4.2BSD (TCP/IP derived from ARPAnet),
    4.3BSD (still for VAX, XNS), 4.3BSD-Tahoe (portable, for Tahoe = CCI Power 6/32), (documents),
    Net/1 ("Berkeley Networking Distribution", freely distributable networking code of 4.3BSD-Tahoe),
    4.3BSD-reno (interim release before 4.4BSD, for VAX/Tahoe/HP9000-300, NFS, download),
    Net/2 (freely distributable code of 4.3BSD-reno, almost complete distribution: "six missing files" due to 32/V copyrights),
    386/BSD (full freely distributable release for Intel 386 architecture, by Bill Jolitz, own "six missing replacements", info)
    NetBSD/FreeBSD/OpenBSD (derived from Net/2 and 386/BSD, info),
    BSDI (commercially supported version of Net/2 with its own "six files", info),
    4.4BSD-Encumbered (with old 32/V copyright), 4.4BSD-Lite (freely distributable, base for rework of BSDI/NetBSD/FreeBSD/OpenBSD, announcement, documents, info, download), 4.4BSD-Lite Release 2 (bug fix of 4.4BSD-Lite, info)

    some currently available BSD releases:
    4.4BSD-Lite Release 2 (multiplatform)
    NetBSD (most platforms, ftp),
    OpenBSD (multiplatform, improved security, ftp),
    FreeBSD (especially for i386/alpha, ftp)
    2.11BSD (for PDP-11/xx with 22-Bit addressing, mainly a 4.3BSD port)

  • Mach (UNIX-like operating system, based on BSD, by Carnegie Mellon University, 1985-1994, with Mach Microkernel)

    Mach decendents:
    OSF/1 (by OSF)
    The Open Group: Mk
    4.4BSD on Mach: Lites

  • POSIX (Portable Operating System Interface, IEEE 1003.x standards, heavily influenced by UNIX, certification)

  • X Window System (GUI + protocol, developed at MIT as part of "Project Athena distributed workstation environment", first implementations on VAXstations, influenced by Stanford windowing system W and Sun's SunView)
    Look&Feels: X-MIT Athena, Sun & AT&T OpenLook, OSF Motif, DEC DECwindows, SGI 4Sight,
    Xfree86 (freely redistributable open-source implementation, first versions for Intel x86 platforms, now multiplatform)

  • The Open Group:
    Formed in 1996 of X/Open and OSF

    X/Open Company Ltd.:
    Formed in 1984, standards for open architecture systems (mainly UNIX systems), 1993: "X/Open Portability Guide" (XPG) standards for use of the UNIX brand name (superset of the IEEE/ANSI POSIX, Novell delivered the control of the UNIX name to X/Open in 1993)

    OSF ("Open Software Foundation"):
    Formed in 1988 (mainly by IBM/HP/DEC), alternative to SVR4 (Sun/AT&T), software specifications, products: DCE, Motif, OSF/1

  • OSF/1 (by OSF, system definitions, based on the (BSD-based) Mach and System V, conforms to SVID ("System V Interface Definitions") and UNIX standards, influenced HP-UX/AIX/Digital UNIX)

  • GNU (UNIX-like operating system environment, base environment for Linux and various freely distributable BSDs, stands for "GNU's not UNIX", history, GNU General Public License),
    GNU kernel: HURD (based on Mach Microkernel)
    GNU for HP-UX
    see also: djgpp GNU development system for PCs running DOS

  • MINIX (UNIX-like system, written by Andrew S. Tanenbaum from scratch, ftp)
    MINIX 1.5: PC, amiga, atari, Apple Macintosh,
    MINIX 2.0: PC with 8088/286/386/486/pentium CPU

  • Linux (UNIX-like multiplatform, original kernel written for Intel i386 architecture by Linus Torvalds from scratch, GNU environment, history)
    MkLinux (based on Mach Microkernel)
    Linux HOWTO


    Slackware, MCALinux (Slackware for IBM PS/2 with MicroChannel)
    RedHat (ftp),
    Debian distribution,
    Corel Linux

    drivers, etc.:
    LinuxLabProject (HP-IB drivers, control software for multimeters)

  • ULTRIX (by DEC)
    "ULTRIX-11" for PDP-11 (2BSD based)
    "ULTRIX-32" for VAX (3BSD and 4BSD based), later "ULTRIX VAX"
    "ULTRIX-32m" for MicroVAX, later "ULTRIX VAX"
    "ULTRIX VAX", for VAX/MicroVAX systems
    "ULTRIX MIPS" for MIPS based DECstations/systems
    latest versions mainly 4.2BSD + parts of 4.3BSD and SVR4, DEC picture

  • HP-UX (proprietary UNIX system by HP for their HP9000 series minicomputers/workstations, first releases based on BSD and System V extensions, later mainly SVR4 with influences by OSF/1, HP documentation, free GNU software)

  • AIX (proprietary UNIX system by IBM, influenced by BSD + System V + OSF/1)

  • SunOS (proprietary UNIX system by Sun, first releases heavily influenced by BSD, later shift to System V due to partnership with AT&T, BSD + SunOS + System V gave SVR4)

    Solaris (package of:
    SunOS, Openwindows, Openwindows deskset tools, ONC networking products and services (which includes NFS and NIS))

  • IRIX (proprietary UNIX system by SGI, based on System V)

  • Digital UNIX (formerly "DEC OSF/1 AXP", based on the OSF/1 specification, by DEC (now Compaq) for Alpha AXP based computers),
    Tru64 UNIX (successor of Digital UNIX, by Compaq)

  • OpenVMS (formerly VAX/VMS for VAX processors, older versions: special MicroVMS version for MicroVAX processors, proprietary real-time multi-tasking multi-user OS, "Open"-versions are POSIX compliant, first VMS versions for VAX and since OpenVMS also for Alpha AXP, by DEC (now Compaq)): infos+links, related sites, history, history2, VMS hardware, Hobbyist license,
    tricks and FAQs: tricks1, tricks2, tricks3, tricks4, tricks5, documentation
    DCL (command interpreter language)
    network: DNA, DECnet, ...
    storage devices + cluster: SCA, SCS, MSCP, VAXcluster, ...
    file systems:
    ODS-2 ("On-Disk Structure 2") + RMS ("Record Management Services")
    ODS-1 ("On-Disk Structure 1", see PDP-141, e.g. used for floppies under VMS) accessible via EXCHANGE utility

  • VAXELN (for VAX processors, dedicated stand-alone application multi-tasking system, programming: special Pascal development software under VAX/VMS, by DEC, similar to Micropower Pascal for PDP-11)

  • Digital Research CP/M (single-user single-task operating system, by Gary A. Kildall, infos, info, info + downloads, info)
    CP/M: for Intel 8080 and Zilog Z80 based computers
    CP/M-86: variant for Intel 8086 based computers
    CP/M-68K: variant for Motorola 68000 based computers

    CP/M components/layers:
    CCP ("Console Command Processor"): command line interpreter
    BDOS ("Basic Disk Operating System"): machine independent part
    BIOS ("Basic Input Output System"): machine dependent part

    CP/M descendants:
    86-DOS (and later MS-DOS)
    CP/M-86 descendants:
    DOS plus
    Concurrent DOS
    REAL/32 by IMS Ltd.
    CP/M-68K descendants:

  • Digital Research GEM/GEMDOS
    based on CP/M-68K

    GEM/GEMDOS layers/components
    XBIOS: extension to BIOS
    GEMDOS ("GEM Disk Operating System"): analogous to CP/M BDOS layer
    GEM ("Graphical Environment Manager"): graphical user interface

    GEM components
    AES ("Application Environment System")
    VDI ("Virtual Device Interface")
    GEM Desktop

    used in Apple Lisa and Atari ST (see TOS)

  • Atari TOS ("The Operating System" or "Tramiel Operating System", for 68000 based Atari ST computer, info):
    TOS: ST variants of GEM + GEMDOS (see Digital Research) + XBIOS + BIOS

  • "QDOS", 86-DOS ("Quick and Dirty Operating System", by Tim Paterson (Seattle Computers) for Intel 8086-based computers, largely based on CP/M, first release 1980, info, later bought by Microsoft and became MS-DOS)
    Note: The 86-DOS, which is was called "QDOS" in its first release, has nothing to do with Fairlight's QDOS, which is a variant of Motorola's MDOS for the dual-6800 QASAR computer, (see MDOS for more).

  • MS-DOS (by Microsoft, for Intel x86 based PCs, ancestor: 86-DOS, info)

  • MDOS (by Motorola, for Motorola 6800 based computers, info)


    QDOS: Fairlight QASAR dual-6800 variant of MDOS (1976, click here for more infos about QASAR and QDOS)
    Note: The QASAR QDOS has nothing to do with 86-DOS, which is often referred to as "QDOS" (or "Quick and Dirty Operating System"), written by Tim Paterson for Intel 8086-based computers (see 86-DOS for more). Furthermore, QASAR QDOS has also nothing to do with QDOS for the Sinclair QL (68008-based) computer system.


    Fairlight QDOS

  • OS-9, OS-9000 (by Microware, proprietary real-time multi-user multi-tasking OS, main architecture based on memory modules with CRC protection, infos + manuals)

    OS-9/6809 = OS9: for Motorola 6809 (depending on the presence of virtual memory support: "OS9 Level 1" and "OS9 Level 2")
    OS-9/68K = OSK: for Motorola 680x0 architectures (depending on the presence of virtual memory support: "OSK Level 1" and "OSK Level 2")
    OS-9000 = OS9000 = OS9K: multi-platform successor of OS-9

    Not to be confused with "Mac OS 9" for the Apple Macintosh.

    RBF: "Random Block File", called after the rbf filemanager. (info for OSK)
    OS-9 Level 1 and 2 only use 256-Byte sectors, but some device drivers are able to translate other sector sizes (e.g. 512 or 2048 Bytes) into "virtual" 256-Byte sectors.

    OS-9/NET (optional extension for OS-9/68K for filesystem and device access on remote nodes):
    network filemanager NFM
    eio + netserv processes (started via nmon): incoming message monitor/server
    physical layers:
    * OMNINET (1 Mbps RS-485 multidrop bus, HDLC based)
    * ARCNET ("Attached Resource Computer NETwork", 2.5 Mbps token passing bus)
    * Ethernet (10Mbps CSMA/CD bus, types: 0x7007, 0x7009)
    * RS-232C (point-to-point)

    RTSI OS-9 World Wide Archive
    Fairlight CMI Series III OS-9 Level 2 infos
    Downloads (especially for CMI)

  • NitrOS-9 (OS-9 compatible, for Hitachi 6309)

  • FLEX (disk operating system by TSC)
    MiniFLEX (1976, for Motorola 6800)
    FLEX (MiniFLEX successor)
    FLEX 9 (for Motorola 6809)

    FLEX user group, history
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Designed by K.M. Indlekofer. See disclaimer. Send comments about this site to Klaus Michael Indlekofer. Last updated 11/11/2002.