UNIX is a multi-user and multitasking operating system. in a multi-user environment. the computer can receive the commands from a number of end users programs, access files, and print documents simultaneously.
The host computer, which has a UNIX operating system, provides services to the terminal, such as file access services. four terminals are connected to one host computer and all the terminals are sharing resources from the host computer.
Features of UNIX
The general and additional features of UNIX operating system are :
- File and Processes : file and process are two entities that are supported by UNIX. A file contains information, such as text, code or directory structure that you need to save in the computer, The file is stored in the hard disk of the computer at a particular location, which can be easily remember whereas a process is the name given to a file or a programs that is currently running . UNIX provides various tools that enable you to control a process, change the sequence of the process, and kill the process.
- Multi-user system: UNIX supports multitasking system as the kernel is designed to handle multiple processes. A single user can run multiple process simultaneously. For example, an end user can print a file and edit another file simultaneously. The kernel handles the multiple processes as foreground and background process. The current process runs in the foreground and the other processes run in the background. This multitasking feature is an advantage for the programmers, as they do not have to close the editor and run the program; this can done simultaneously.
- UNIX toolkit: The UNIX toolkit provides various tools that are enable you to perform different tasks in UNIX as kernel alone cannot perform every task. The tools that are included in the UNIX toolkit are:
1:- General purpose tools , such as vi editor
2:- Text manipulation utilizes filters that are used to retrieve the output from two or more commands simultaneously .
3:- Compiler and Interpreter .
4:- Network administration and system tools , such as mailx and pine.
- Pattern Matching :- UNIX supports pattern matching feature that enables you to retrieve the output according to the required pattern . Pattern matching in UNIX can be implemented using a special characters , such as * known as metacharacter .
- Programming Facility :- UNIX provides a programming facility known as shell that is developed specifically for programmers and not for the users .