Operating systems final Multiple choice

_ is a symmetric stream encryption algorithm A) DES B) AES C) RC4 D) RSA E) SSL

C

___ allows the parent and child processes to initially share the same pages, but when either process modifies a page, a copy of the shared page is created A) memory mapping B) zero fill on demand C) copy and write D) virtual memory fork

C

___ is the dynamic storage allocation algorithm which results in the largest leftover hole in memory A) First fit B) Best fit C) Worst fit D) None of these

C

the surface of individual magnetic disk platter is divided into circular regions called ____. A) sectors B) arms C) tracks D) heads E) cylinders

C

which of the following scheduling algorithms is never preemptive? A) SJF B) RR C) FCFS D) priority scheduling

C

In a system resource - allocation graph, ___. A) assume that deadlocks never occur B) use protocols to prevent or avoid deadlocks C) detect and recover from deadlocks D) none of the above

C

LWP is ____. A) short for lightweight processor B) placed between system and kernel threads C) placed between user and kernel threads D) common in systems implementing one-to-one multithreading models

C

The SSTF scheduling algorithm_. A) services the next request in the current direction of head travel B) services the request with the maximum seek time C) services the request with the minimum seek time D) none of the above

C

Which of the following would lead you to believe that a given system is an SMP-type system? A) There is a master-slave relationship between the processors B) Each processor is assigned a specific task C) Each processor can perform all tasks within the operating system D) None of the above

C

A _ virus attempts to avoid detection by modifying parts of the system that could be used to detect it A) polymorphic B) tunneling C) multipartite D) stealth

D

A ___ uses an existing thread rather than creating a new one to complete a task A) Lightweight process B) remote procedure call C) scheduler activation D) thread pool

D

A mount point is _. A) only appropriate for the shared file systems B) a location within a shared file system C) the root of the overall file system D) the location within the file structure where a given file system is to be attached

D

A process control block ___ A) stores the address of the next instruction to be processed by a different process B) determines which process is to be executed next C) is an example of a process queue D) includes information on the process's state

D

The Windows CreateProcess() system call creates a new process. What is the equivalent system call in UNIX? A) exc() B) UxCreateProccess() C) process() D) fork()

D

The mapping of a logical address to a physical address is done in hardware by the ___ A) address generation chip B) relocation register C) physical address translation device D) memory-management unit

D

Which of the following would be an acceptable signal handling scheme for a muktithreaded program? A) Deliver the signal to the thread to which the signal applies B) Deliver the signal to every thread in the process C) Deliver the signal to only certain threads in the process D) All of the above

D

Worms _. A) use the spawn mechanism to ravage system performance B) can shut down an entire network C) continue to strike as the Internet expands D) all of the above

D

_ is an asymmetric block encryption algorithm A) DES B) AES C) RC4 D) RSA E) SSL

D

___ Provides an interface to the services provided by an operating system A) Communication B) Simulators C) Shared memory D) System calls

D

A semaphore ___. A) cannot be used to control access to a thread's critical sections B) is accessed through two standard operations C) can be modified simultaneously by multiple threads D) is essentially a real-number variable

B

A surreptitious access mechanism left behind by the creator of a program/ system is called _. A) a backdoor B) a trap door C) a Trojan horse D) a worm

B

A(n) _ is a buffer that holds output for a device that cannot accept interleaved data streams A) escape B) spool C) cache D) block buffer

B

An ___ page table has one page entry for each page frame of physical memory A) clustered B) inverted C) forward - mapped D) multi - level

B

An ___ refers to where a process is accessing/updating shared data A) entry section B) critical section C) adaptive mutex D) test and set

B

Another necessary condition for deadlock is ___, which states that at least one resource must be held in a non-shareable mode. A) hold and wait B) mutual exclusion C) circular wait D) no preemption

B

Assume a system uses base and limit registers to control access to memory and their current values are 1200 and 350, respectively. Which of the following addresses is legal for the program to access A) 400 B) 1300 C) 1551 D) all of these E) none of these

B

Optimal page replacement ____. A) is the page-replacement algorithm most often implemented in real systems B) is used mostly for comparison with other page-replacement schemes C) can suffer from Belady's anomaly D) requires that the system keep track of previously used pages

B

The ___ multithreading model maps a number of user level threads to an equal number of kernel threads A) many to one B) one to one C) many to some D) many to many

B

The ___ occurs in the FCFS scheduling when a process with a long CPU burst occupies the CPU A) dispatch latency paradox B) convoy effect C) system-connection scope problem D) context switch overload

B

The ___ occurs in the first come first serve scheduling when a process with a long CPU burst occupies the CPU A) dispatch latency paradox B) convoy effect C) system-contention scope problem C) context switch overhead

B

Which of the following disk head schedualing algorithims does not take into account the current position of the disk head? A) SSTF B) FCFS C) SCAN D) LOOK

B

___ scheduling is approximated by predicting the next CPU burst with an exponential average of the measured lengths of previous CPU bursts A) Multi level queue B) SJF C) RR D) FCFS

B

A Java thread may release a lock under which of the following circumstances? A) it exists a synchronized method B) It invokes the notify() method C) It invokes the wait() method D) Both (A) and (B)

B

A ___ is an example of a systems program A) web browser B) command interpreter C) text formatter D) database system

B

A deadlock state occurs whenever ___. A) Process is waiting for I/O to a device that does not exist B) every process in a set is waiting for an event that can only be caused by another process in the set C) the system has no available free resources D) a process is unable to release its request for a resource after use

B

A denial of service attack is _. A) aimed at gaining information B) aimed at disrupting legitimate use of a system C) aimed at stealing resources D) generally not network based

B

___ is not a technique for passing parameters from an application to a system call. A) Cache memory B) Registers C) Stack D) Special block in memory

A

___ occurs when a process spends more time paging than executing A) thrashing B) Memory mapping C) Swapping D) Demand paging

A

In an access matrix, the _ right allows a process to change the entries in a row A) control B) copy C) owner D) switch

A

Mechanism ___ A) determines how to do something B) determines what will be done C) should be coupled tightly to policy D) is likely to change frequently

A

The default scheduling class for a process in Solaris is __? A) time sharing B) system C) interactive D) real time

A

The default scheduling class for a process in Solaris is ___ A) time sharing B) system C) interactive D) real time

A

The file allocation table (FAT) scheme used in MS-DOS and supported by windows is a modified version of _. A) linked allocation B) indexed allocation C) hashed allocation D) contigous allocation

A

To handle deadlocks in application programs, operating systems most often ___ A) assume deadlocks never happen B) use protocols to prevent or avoid deadlocks C) detect and recover from deadlocks D) none of the above

A

To the SYSGEN program of an operating system, the least useful piece of information is ___. A) what applications to install B) the CPU being used C) the amount of memory available D) operating-system options such as buffer sizes or CPU scheduling algorithms

A

A(n) is used in many file systems at the end of a file name to indicate the type of the file A) extension B) Creator name C) Hint D) Magic number E) none of these

A

A _ is a public key digitally signed by a trusted party A) digital certificate B) key ring C) message digest D) digital key

A

A ___ virus changes each time it is installed to avoid detection by anitviurs software A) polymorphic B) tunneling C) multiparithitic D) stealth

A

A contiguous chunk of disk blocks is known as a(n) _. A) extent B) disk block group C) inode D) FAT

A

A race condition ____. A) results when several threads try to access the same data concurrently B) results when several threads try to access and modify the same data concurrently C) will result only if the outcome of execution does not depend on the order in which instructions are executed D) None of the above

A

A shared file lock_. A) behaves like a reader lock B) Ensures that a file can have only one concurrent shared lock C) behaves like a writer lock D) Can allow selected other processes to access the locked file

A

The most common technique for writing multithreaded Java programs is ___. A) implementing the Runnable interface and defining its run() method B) extending the Thread class and overriding the run() method C) designing your own Thread class D) using the CreateThread() function

A

The tracks on a magnetic disk surface are divided into smaller regions called _. A) sectors B) arms C) tracks D) cylanders E) heads

A

Thread-specific data is data that ___. A) is copied and not shared with the parent process B) is not associated with any process C) has been modified by the thread, but not yet updated to the parent process D) is created by the parent process and shared with the threads

A

In Linux and other UNIX-based operating systems, which of the following is not considered a classification of users with respect to each file A) owner B) current user C) group D) universe

B

5) A volume control block_. A) can contain information needed by the system to boot an operating system from that partition B) is the directory structure used to organize the files C) contains information such as the number of blocks in a partition, size of blocks, and free-block and FCB count and pointers D) contains many of the file's details, including file permissions, ownership, size, and location of the data block

C

A ___ saves the state of the currently running process and restores the state of the next process to run A) save-and-restore B) state switch C) context switch D) none of these

C

A code segment that misuses its environment is called _. A) a backdoor B) a trap door C) a Trojan horse D) a worm

C

A spinlock ___. A) is only advantageous on uniprosessor system B) will ultimately result in a context switch when a process must wait on a lock C) does not require a context switch when a process must wait on a lock D) is useful when locks are expected to be held for long amounts of time

C

An exclusive file lock_. A) behaves like a reader lock B) Ensures that a file can have only one concurrent shared lock C) behaves like a writer lock D) Can allow selected other processes to access the locked file

C

Belady's Anomaly is the observation that ______. A) giving more memory to a process will improve its performance B) as the number of allocation frames increases, the page fault rate may decrease for all page replacement algorithms C) for some PGAs, the page - fault rate may increase as the number of allocated frames increases D) for some PGAs, the page - fault rate may decrease as the number of allocated frames increases

C

Consider a system with a page size of 8 KB. How many bits must be used to represent the offset within a page A) 10 B) 8 C) 13 D) 12

C

How many philosophers may eat simultaneously in the Dining Philosophers problem with 7 philosophers? A) 1 B) 2 C) 3 D) 4 E) 5 F) all 7

C

Embedded computers typically run a ___ operating system A) Windows B) network C) clustered D) real - time

D

In a paired password system, _. A) the user specifies the two passwords B) two user must enter their own separate passwords to gain access to the system C) passwords must contain equal amounts of numbers and digits paired together D) the computer supplies one part of a password and the user enters the other part

D

On time-slicing systems, a runable Java thread will continue executing until which of the following events occurs? A) Its time quantum expires B) It blocks for I/O C) It exists its run() method D) Any events A through C

D

One necessary condition for deadlock is ______, which states that a resource can be released only voluntarily by the process holding the resource A) hold and wait B) mutual exclusion C) circular wait D) no preemption

D

What are the two largest components of positioning time for a disk A) cylinder positioning time + disk arm positioning B) transfer time + transfer rate C) effective transfer rate - transfer rate D) seek time + rotational latency E) none of the above

D

Which of the following allocation methods ensures that only one access is needed to retrieve data from a block belonging to a file on disk when performing direct access?A) linked allocation B) indexed allocation C) hashed allocation D) contiguous allocation

D

Which of the following is a benefit of allowing a program that is only partially in memory to execute? A) Programs can be written to use more memory that is available in physical memory B) CPU utilization and throughput is increased C) Less I/O is needed to load or swap each user program into memory D) all of the above

D

Which of the following is true of the Java programming language in a relation to protection A) methods in the calling sequence are not responsible for requests to access a protected resource B) it does not support the dynamic loading of untrusted classes over a nwtwork C) it does not support the execution of the mutually distrusting classes within the same JVM D) When a class os loaded, the JVM assigns the class to a protection domain that gives the permissions of that class

D