Operating Systems Questions

When a process requests an available resource, system must decide if immediate allocation leaves the system in a safe state. System is in safe state if there exists a safe sequence of all processes. Deadlock Avoidance : ensure that a system will never enter an unsafe state.

Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel. By default, a Linux user falls under same as userid (UPG) group.

$pwd - present working directory

C++ is not an Operating System.

An Operating System is a collection of system programs that manages all the other programs application programs in a computer as well as the allocation and use of hardware resources such as the CPU, Memory and the Hard Disk Drive.

It acts as an interface between the hardware and the user level program.

It controls and facilitates the overall operation of a computer. 

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UNIX : UNIX is a popular multi-user, multitasking operating system (OS) developed at Bell Labs.

Windows NT : Windows NT is a family of operating systems produced by Microsoft, the first version of which was released in July 1993.

DOS : DOS is Disk Operating System. The term DOS can refer to any operating system.

C++ : C++ is a programming language and computing platform.

Hence, C++ is not an Operating System.

The given statement is clearly true.

A bootstrap is the process of starting up a computer. It also refers to the program that initializes the operating system (OS) during start-up.

It referred to a bootstrap load button that was used to initiate a hardwired bootstrap program, or smaller program that executed a larger program such as the OS.

In a cached system, the base addresses of the last few referenced pages is maintained in registers called the TLB that aids in faster lookup. TLB contains those page-table entries that have been most recently used. Normally, each virtual memory reference causes 2 physical memory accesses- one to fetch appropriate page-table entry, and one to fetch the desired data. Using TLB in-between, this is reduced to just one physical memory access in cases of TLB-hit.

The perfect paging size varies from system to system, so there is no single best when it reaches to page size. There are several factors to consider in order to come up with a fitting page size, such as paging time, page table, and its effect on the total performance of the operating system.