IV. Make up sentences and identify the purpose of an operating system

III. Make up word combinations.

II. Translate the following word combinations.

Command Interpreter System

Protection System

Networking

A distributed system is a collection of processors that do not share memory, peripheral devices, or a clock. The processors communicate with one another through communication lines called network. The communication-network design must consider routing and connection strategies, and the problems of contention and security.

If a computer system has multiple users and allows the concurrent execution of multiple processes, then the various processes must be protected from one another's activities. Protection refers to mechanism for controlling the access of programs, processes, or users to the resources defined by a computer system.

A command interpreter is an interface of the operating system with the user. The user gives commands with are executed by operating system (usually by turning them into system calls). The main function of a command interpreter is to get and execute the next user specified command. Command-Interpreter is usually not part of the kernel, since multiple command interpreters (shell, in UNIX terminology) may be support by an operating system, and they do not really need to run in kernel mode. There are two main advantages to separating the command interpreter from the kernel.

If we want to change the way the command interpreter looks, i.e., I want to change the interface of command interpreter, I am able to do that if the command interpreter is separate from the kernel. I cannot change the code of the kernel so I cannot modify the interface.

If the command interpreter is a part of the kernel it is possible for a malicious process to gain access to certain part of the kernel that it showed not have to avoid this ugly scenario it is a dvantageous to have the command interpreter separate from kernel.

operating system, system components, system calls, multiple command interpreter, specified command, communication-network design, to consider routing and connection strategies, problems of contention and security, complete execution context, processes suspension and resumption, process synchronization mechanism, process communication mechanism, deadlock handling mechanism, memory access, allocation of storage space, kernel mode.

1. to share _____________;

2. to support ____________;

3. to include_______________;

4. to get and execute______________;

5. to run ______________________;

6. to create and delete __________________;

7. to suspend and resume _______________;

8. to synchronize ________;

9. to handle ____________________.

1. software /System / the use of a /facilitates/ computer system.

2. to communicate/ An OS /is system software/ the application software./that enables/ the computer hardware/ and operate with /

3. cannot/Without / a computer / an operating system, /function.

4. and coordinates activities/ manages/The operating system/ and resources of the computer.

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