The Operating System,Lesson One Summary of operating system,An operating system serves as an interface, bridging the gap between hardware and application software. Thus, as we move from hardware to software, its appropriate that we consider the operating system first.,serve 服务，供应 interface 界面 bridge n.桥；vt.架桥 gap n.缺口，缝隙 thus adv.因而，从而，如此 appropriate adj.适当的 consider vt.考虑，照顾，认为,What exactly dose an operating system do? Basically, it performs a number of support functions. exactly basically support,adv.正确地 严密地,adv.基本上 主要地,v.支持，维持 n.支持，支持者,If the application program is to be loaded, there must be a program in memory to control the loading process. That program is the operating system. Typically, the operating system is stored on disk. This objective is achieved by a special program called a boot.,adv.代表性地,n.目标，目的 adj.客观的,v.完成，到达,Generally, the boot is stored on the first sector (or two) of a disk. Hardware is designed to read this sector automatically whenever the power is turned on. The boot consists of only a few instructions, but they are sufficient to read the rest of the operating system into memory; note how it is seemingly “pulled in by its own bootstraps”. Now, a user can type the commands to load and execute an application program.,generally sector designed automatically consists of instructions sufficient,rest note seemingly own type load execute,Loading programs is only one of the operating systems many support functions. Basically, it is a collection of software modules that insulate the user from the hardware, thus making the system easier to use. Lets investigate the primary functions of a typical operating system.,collection n.收藏，搜集品 module n.模块 insulate vt.使绝缘，隔离 investigate v.调查，研究 primary adj.第一位的，主要的,The operating system is a collection of programs designed to manage the systems resources, namely, memory, processors, devices, and information (program and data).,n.资源，财力，办法，智谋,Memory Management Functions Keep track of the memory. What parts are in use and by whom? What parts are free? If multiprogramming, decide which process gets memory, when it gets it and how much. Allocate the memory, and reclaim the memory when the process no longer needs it or has been terminated.,keep track of 明了 free adj.自由的，免费的，空闲的 multiprogramming 多道程序 allocate vt.分派，分配 reclaim vt.要求归还，收回 no longer 不再 terminate v.停止，结束，终止,Processor Management Function Keep track of the processors and the status of processes. Decide who will have a chance to use the processor. If multiprogramming, decide which process gets the processor, when and how much. Allocate the processor to process by setting up necessary hardware registers, this is often called the dispatcher. Reclaim the processor when process terminates, or exceeds allowed amount of usage.,status n.身份，地位，状况 chance n.机会，可能性 setting up 设立 necessary adj.必要的 register 记录，登记 dispatcher n.发报机 exceed v.超越，胜过 allow vt.允许，承认,Device Management Functions Keep track of devices, channels, control units, this is called the traffic controller. Decide what an efficient way to allocate the device is. If it is to be shared, then decide who gets it, and how much he is to get, this is called I/O scheduling. Allocate the device and initiate the I/O operation. Reclaim the device. In most cases, the I/O terminates automatically.,channel n.水道，路线；vt.引导，开导 control unit 控制单元 traffic 交通 share 分享，共享 scheduling 行程安排，时序安排 initiate v.开始 case 情形，事，案例,Information Management Functions Keep track of the information, its location, use, status, etc. Decide who gets use of the information, enforce protection requirements, and provide accessing routines. Allocate the information, and reclaim the resource.,location n.位置，场所 enforce vt.强迫，执行，加强 protection n.保护 requirement n.需求，要求，必要条件 provide v.供应，供给，准备 routine n.例行公事，程序，日常事务,Single choice. 1. The serves as a hardware/software interface. a. system c. control unit b. application program 2. The source of a computers logic is . a. hardware c. data d. the user 3. Most microcomputer operating system are driven. a. interrupt b. command d. hardware,d. operating system,b. software,c. software,4. A user communicates with the operating system through . a. instructions c. hardware b. a program 5. The operating system is loaded by . a. the command processor c. the program loader d. an interrupt,b. a boot,d. a command language,1.Eating to live is more meaningful than living to eat. 为了活而吃比为了吃而活更有意义。 2.Shouting English is very helpful conquering your shyness. 大喊英语对克服你的羞怯心理很有帮助。 3.Arguing with you all the time makes me tired. 老是跟你争吵使我厌烦。 4.Eating too much can make you fat.吃得过多会使你发胖。 5.Smoking causes a lot of health problems. 吸烟会导致多种健康问题。 6.Getting married costs a lot. Getting divorced costs much more. 结婚很贵，离婚更贵。,英语口语练习材料,Lesson Two DOS,DOS is an acronym for Disk Operating System. It is a popular operating syst