Lecture Operating system - Chapter 10: Case study 1 - Unix and Linux has contents: History of unix, overview of unix, processes in unix, memory management in unix, input/output in unix, the unix file system, security in unix.
Trang 1Case Study 1: UNIX and LINUX
Chapter 10
10.1 History of unix 10.2 Overview of unix 10.3 Processes in unix 10.4 Memory management in unix 10.5 Input/output in unix
10.6 The unix file system 10.7 Security in unix
Trang 3UNIX Utility Programs
A few of the more common UNIX utility programs required by POSIX
Trang 4UNIX Kernel
Approximate structure of generic UNIX kernel
Trang 5Processes in UNIX
Process creation in UNIX
Trang 6POSIX
The signals required by POSIX
Trang 8POSIX Shell
A highly simplified shell
Trang 9Threads in POSIX
The principal POSIX thread calls
Trang 10The ls Command
Steps in executing the command ls type to the shell
Trang 11Flags for Linux clone
Bits in the sharing_flags bitmap
Trang 12UNIX Scheduler
The UNIX scheduler is based on a multilevel queue structure
Trang 13Booting UNIX
The sequences of processes used to boot some systems
cp
Trang 15Sharing Files
Two processes can share a mapped file
A new file mapped simultaneously into two processes
Trang 17Paging in UNIX
The core map in 4BSD
The core map has an entry for each page
Trang 18Paging in Linux (1)
Linux uses threelevel page tables
Trang 19Paging in Linux (2)
Operation of the buddy algorithm
Buddy algorithm
Trang 20Networking
Use of sockets for networking
Trang 21Terminal Management
The main POSIX calls for managing the terminal
Trang 22UNIX I/O (1)
Some of the fields of a typical cdevsw table
Trang 23UNIX I/O (2)
The UNIX I/O system in BSD
Trang 24Streams
An example of streams in System V
Trang 25The UNIX File System (1)
Some important directories found in most UNIX systems
Trang 30The lstat System Call
Fields returned by the lstat system call
Trang 32UNIX File System (1)
Disk layout in classical UNIX systems
Trang 33UNIX File System (2)
Directory entry fields
Structure of the inode
Trang 34UNIX File System (3)
The relation between the file descriptor table, the open file description
Trang 36The Linux File System
Layout of the Linux Ex2 file system
Trang 37Network File System (1)
• Examples of remote mounted file systems
• Directories are shown as squares, files as circles
Trang 38Network File System (2)
The NFS layer structure
The NFS layer structure
Trang 39Security in UNIX
Some examples of file protection modes
Trang 40System Calls for File Protection
• s is an error code
• uid and gid are the UID and GID, respectively