Which of the following is not the feature of UNIX operating system?
Single tasking is not the feature of UNIX operating system.
Single-tasking operating system is one that allows only a single user to perform a single task at a time. A task is a function such as reading a file from disk, performing a math calculation, printing a document, or sending a request over the Internet to a Web server. While a multi-tasking operating system allows more than one program to be running in concurrency.
The UNIX operating system is a set of programs that act as a link between the computer and the user. The computer program that allocates the system resources and coordinate all the details of the computer's internals is called the operating system or the kernel.