1. Introduction 1 Chapter 1. Introduction History and Proliferation Mandate for Change What’s Good and Wrong Scope of this course

2. Introduction 2 History of UNIX Late 1960s, Bell Telephone Lab. –Project with GE and MIT: Multics –Multics was canceled in March 1969 –Ken Thompson: Space Travel game program –UNIX on PDP-7 (DEC) –PDP-11, B language –1973, released C compiler cc –1973, rewritten in C (version 4 UNIX)

3. Introduction 3 Proliferation of UNIX 1973, UC Berkeley obtained UNIX 1979, Version 7 UNIX (portable UNIX) Microsoft and SCO: XENIX on Intel 8086 1978, DEC 32-bit VAX-11 computer –UNIX on VAX: UNIX/32V –UC Berkeley: 3BSD, 1979

4. Introduction 4 Berkeley Software Distribution 3BSD, 1979 –paging-based virtual memory (on VAX-11) 4BSD by DARPA project –Integrate TCP/IP, 4.0 BSD in 1980 –4.1 BSD in 1981, 4.2 BSD in 1983 –4.3 BSD in 1986 –4.4 BSD in 1993 –UC Berkeley discontinue UNIX development

5. Introduction 5 System V Bell Telephone Lab. –System III in 1982 –System V in 1983 virtual memory different from BSD –System V Release 2 (SVR2) in 1984 –SVR3 in 1987 interprocess communication –SVR4 in 1989 security and multiprocessor

6. Introduction 6 Commercialization Sun Microsystems –SunOS in 1982 (4.2 BSD-based) Network File System (NFS) –Solaris (SVR4-based) MS, SCO –XENIX, SCO UNIX IBM: AIX, HP: HP-UX DEC: ULTRIX –first multiprocessor UNIX

7. Introduction 7 Mach In mid-1980s, Carnegie-Mellon University Microkernel –small set of essential services –other functions at the user level Uni- and Multi-processor Distributed environment Mach 3.0: OSF/1 and NextStep

8. Introduction 8 Standards of UNIX Initially: AT&T System V and BSD. System V Interface Definition (SVID) –System V-based IEEE POSIX Spec. –Portable Operating Systems based on UNIX –amalgam of core parts of SVR3 and 4.3BSD –POSIX.1 in 1990 X/Open Portability Guide –based on POSIX.1

9. Introduction 9 OSF and UI Open Software Foundation –1988: DEC + IBM + HP … –free of AT&T license encumbrances –1989, Motif GUI –OSF/1 based on Mach 2.5 Unix International –AT&T + Sun –marketing SVR4 1990s, economic downturn + MS Windows

10. Introduction 10 Mandate for Change Functionality: e.g. IPC Networking: e.g. NFS, NIS, DCE Performance: e.g. Fast file system Hardware Changes: e.g. Multiprocessor, RAID Quality improvement Paradigm shifts –from centralized to distributed (client-server)

11. Introduction 11 Traditional UNIX kernel file system (s5fs) virtual memory loader (a.out) block driver switch disk driver tape driver character driver switch printer driver network driver tty driver kernel

12. Introduction 12 Modern UNIX kernel common facilities exec switch vnode/vfs interface scheduler framework STREAMS block device switch virtual memory framework NFS FFS s5fs RFS time-sharing processes real-time processes system processes tty driver network driver tape driver disk driver file mappings device mappings anonymous mappings a.out coff elf

13. Introduction 13 Good about UNIX License and source code UC Berkeley small and well-designed simple file system uniform I/O interface portability

14. Introduction 14 Wrong with UNIX lack of a simple, uniform GUI variants of UNIX standardization vs. product differentiation bad for code reuse kernel became bloated, unmodular, and complex

15. Introduction 15 Scope of the Course Modern UNIX systems Baseline systems –System V, 4BSD, and Mach Variant systems –SunOS, Solaris 2.x, AIX, HP-UX, ULTRIX, … Term project: MS Windows NT