

According to the classification of operating systems, what is the UNIX operating system?
According to the classification of operating systems, the UNIX operating system is a time-sharing operating system. A time-sharing operating system is an operating system that enables a computer to serve several, dozens or even hundreds of users at the same time using time slice rotation. Typical examples of time-sharing operating systems are Unix and Linux operating systems. It can connect to multiple terminals at the same time and rescan processes at regular intervals, reassign process priorities, and dynamically allocate system resources.
#The operating environment of this tutorial: linux7.3 system, Dell G3 computer.
According to the classification of operating systems, the UNIX operating system is a time-sharing operating system.
Unix is an operating system that appeared in the early 1970s. In addition to being a network operating system, it can also be used as a stand-alone operating system. Unix is widely used as a development platform and desktop operating system, mainly in engineering applications and scientific computing.
The UNIX system is a time-sharing system. The earliest UNIX system came out in 1970. Previously, there were only operating systems for batch jobs, which were too slow for users who needed immediate responses. In the late 1960s, both Kenneth Thompson and Dennis Ritchie participated in the design of the interactive time-sharing system Multics, and the tool used to develop the system was CTSS. Both systems had a major impact on the development of operating systems. On this basis, in the process of refining and developing the existing technology at the time, K. Thompson developed the UNIX system on a small computer in 1969 and put it into operation in 1970.
Time-sharing operating system is an operating system that enables a computer to serve several, dozens or even hundreds of users at the same time using time slice rotation.
Connect the computer to many end users. The time-sharing operating system switches the system processor time and memory space to the programs of each end user in turn at certain time intervals. Because the time intervals are short, each user feels as if he has the computer to himself. The characteristic of time-sharing operating system is that it can effectively increase resource usage. For example, UNIX systems use deprived dynamic priority CPU scheduling to effectively support time-sharing operations.
Typical examples of time-sharing operating systems are Unix and Linux operating systems. It can connect to multiple terminals at the same time and rescan the process at regular intervals, reassign the priority of the process, and dynamically allocate system resources.
Characteristics of time-sharing operating systems
Interactivity (simultaneity): Users engage in human-computer dialogue with the system. Users can directly input, debug and run their own programs on the terminal. On the local computer, they can modify errors in the program and obtain results directly.
Multi-channel (multi-user simultaneity): Multiple users use the same CPU and other resources on their respective terminals at the same time, giving full play to the efficiency of the system.
Independence: Users can operate independently of each other without interfering with or confusing each other.
Timeliness: Users can get timely answers from the system in a short period of time.
Factors that affect the response time: the number of terminals, the size of the time slice, the amount of information exchange, and the speed of information exchange.
Advantages of time-sharing operating system
1) Provide users with a friendly interface, that is, users can get responses in a shorter time, Ability to write, debug, modify, run, and obtain calculation results of programs in a conversational manner.
2) Promotes the popularization and application of computers. A time-sharing system can carry multiple terminals and be used by multiple users near and far at the same time. This provides great convenience for teaching and office automation.
3) Facilitate resource sharing and information exchange, and provide a good environment for software development and engineering design.
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