Question No: 1 (Marks: 1) - Please choose one A computer system that allows only one user to use the computer at a given time is known as:

Transcription

1 MUHAMMAD FAISAL MIT 4 th Semester Al-Barq Campus (VGJW01) Gujranwala faisalgrw123@gmail.com Solved Reference MCQ s For Mid TERM EXAMS CS604 OPERTING SYSTEM Question No: 1 (Marks: 1) - Please choose one A computer system that allows only one user to use the computer at a given time is known as: Single-user system (Page#4) Batch Systems Multi-programmed Systems All of the above options Question No: 2 (Marks: 1) - Please choose one Preventing a condition of to happen, deadlocks can be prevented to happen. Critical region Circular wait Monitors Critical section (Page#136)

2 Question No: 3 (Marks: 1) - Please choose one Operating System provides services such as Managing Primary and Secondary Storage, Processes and Allowing user to manage his/her files and directories. True False (Page#5) Question No: 4 ( Marks: 1 ) - Please choose one The priorities of processes in Group remain fixed whereas the priorities of processes in the Group are recalculated every second. Kernel, Kernel User, Kernel User, User Kernel, User (Page#93) Question No: 5 (Marks: 1) - Please choose one Consider a scenario of CPU protection, is added to the operating system in order to detect and avoid loop in a user program. I/O Timer (page#11) Base and limit registers Turning interrupt enable off Question No: 6 (Marks: 1) - Please choose one Which part of the computer system helps in managing the file and memory management system? Operating System (Page#5) Device Drivers Application Software Hardware

3 Question No: 7 (Marks: 1) - Please choose one A computer system can be divided roughly into four components: The software, the operating system, the application programs and the users The hardware, the operating system, the application programs and the users The hardware, the operating system, the application programs and the s The hardware, the database system, the application programs and the users Question No: 8 (Marks: 1) - Please choose one The Home Directory for superuser in Linux and Unix is: /home /root (Page#27) /usr None of the given Question No: 9 (Marks: 1) - Please choose one scheduler takes the process from the ready queue and assign the CPU with the help of Dispatcher. Long term Short term Medium term Swapper (Page#80) Question No: 10 (Marks: 1) - Please choose one A time-sharing system is multi-user, multi-process, and interactive system. Time-sharing systems Real time systems Both of the above None of the given (Page#6)

4 Question No: 11 (Marks: 1) - Please choose one When processes communicate with each other, they perform communication through synchronization and utilizing separate address spaces. This action is termed as. Process synchronization Message Passing System Direct Communication Inter-process Communication (IPC) (Page#43) Question No: 12 (Marks: 1) - Please choose one Managing Secondary Storage Involves all of the Following except: Allocating storage space Deallocating Storage Prevent Overwritting (Page#5) Insure integrity of shared data Question No: 13 (Marks: 1) - Please choose one We use function to create a thread. fork() thread() mkfifo() open() (Page#71) Question No: 14 (Marks: 1) - Please choose one A signal is an event generated to get attention of a process. Trap Signal (Page#7) Kernel None of the given

5 Question No: 15 (Marks: 1) - Please choose one Files that start with a in UNIX/Linux directory structure are known as hidden files.. (dot) (Page#28) # (hash) / (slash) ~ (tilt) Question No: 16 (Marks: 1) - Please choose one command is used to change the directory. ls cp cd mv (Page#221) Question No: 17 (Marks: 1) - Please choose one holds the smallest legal physical memory address for a process. Base Register (Page#10) Limit register Both of the above options None of these Question No: 18 (Marks: 1) - Please choose one Command-line interpreter is often known as the. register shell kernel timer (Page#16)

6 Question No: 19 (Marks: 1) - Please choose one In system call that creates a pipe for IPC. If one of the operation from read/write would fail then what will be returned as result? -1, +1-1 (Page#47) 1 0 Question No: 20 (Marks: 1) - Please choose one scheduler selects the process from the job pool and put them in main memory. Long term (Page#36) Short term Medium term Swapper Question No: 21 (Marks: 1) - Please choose one The interface between the user and operating system is known as: Command-line interpreter (shell) (Page#13) Protection system Networking File management Question No: 22 (Marks: 1) - Please choose one command to resume the execution of a suspended job in the foreground. fg (Page#68) bg jobs kill

7 Question No: 23 (Marks: 1) - Please choose one User mode can run the Privileged instructions: True (Page#9) False Question No: 24 (Marks: 1) - Please choose one The hardware mechanism that enables a device to notify CPU is called. Interrupt (Page#7) Signal Trap Process Question No: 25 (Marks: 1) - Please choose one Which one of the following indicates end of the file in a read ( ) system call? -1 (Page#51) Question No: 26 (Marks: 1) - Please choose one is used in real time operating systems. Non-preemptive scheduling (Page#80) Preemptive scheduling Dispatching scheduling FCFS scheduling

8 Question No: 27 (Marks: 1) - Please choose one is used to request the OS by the process to take an I/O or initiating child process. System call (Page#15) Interrupt Trap Signal Question No: 28 (Marks: 1) - Please choose one The Operating system is a layer of software between and. Hardware, Software application (Page#21) Kernel, hardware Dos, Windows Windows, Kernel Question No: 29 (Marks: 1) - Please choose one Which one of the following is the correct syntax to copy file1 to file2? cp file2, file1 cp file1/file2 cp file2 file1 cp file1 file2 (Page#30) Question No: 30 (Marks: 1) - Please choose one Linux is a version of operating system. Unix (Page#22) OS/2 Windows None of the above

9 Question No: 31 (Marks: 1) - Please choose one provide the interface between a process and the OS. System Call (Page#15) Signal Interrupt Trap Question No: 32 (Marks: 1) - Please choose one The process of switching from one process to another is called. scheduling latency quantum period context switching (Page#34) Question No: 33 (Marks: 1) - Please choose one System calls can be categorized into the how many groups? (Page#15) Question No: 34 (Marks: 1) - Please choose one The main characteristic of a Real time system is: Efficiency Large Virtual Memory Large secondary storage device Usability (Page#7)

10 Question No: 35 (Marks: 1) - Please choose one Which of the following command is used to read data from file named academics? con < academics cat < academics (Page#58) socket > academics None of the given Question No: 36 (Marks: 1) - Please choose one N-process critical section problem can be solved by using: The bakery algorithm (Page#105) Deterministing modeling Analytic evaluation None of above Question No: 37 (Marks: 1) - Please choose one loads, verifies, and executes programs that have been translated into Java Bytecode. Java Virtual Machine (JVM) (Page#20) Non Virtual Machine Virtual PC None Question No: 38 (Marks: 1) - Please choose one A is an integer variable that, apart from initialization is accessible only through two standard atomic operations: wait and signal. Semaphore (Page#111) Monitor Critical region Critical section

11 Question No: 39 (Marks: 1) - Please choose one determine what will be done. 1) Mechanism 2) Policy (Page#21) 3) Implementation 4) Design Question No: 40 (Marks: 1) - Please choose one scheduling algorithm is sometimes called shortest remaining time first scheduling algorithm. 1) Non-preemptive SJF 2) Priority Scheduling 3) Preemptive Shortest Job First (Page#85) 4) FCFS Question No: 41 (Marks: 1) - Please choose one Often used for storage of large applications packages. 1) /tmp 2) /root 3) /opt (Page#24) 4) /mnt Question No: 42 (Marks: 1) - Please choose one Starvation is infinite blocking caused due to unavailability of resources. 1) True (Page#115) 2) False Question No: 43 (Marks: 1) - Please choose one Typically the execlp system call is used after a fork system call. 1) True (Page#39) 2) False

12 Question No: 44 (Marks: 1) - Please choose one The view is a program that acts as an intermediary between a user of a computer and the computer hardware, and makes the computer system convenient to use. 1) Top-down (Page#6) 2) Bottom-up 3) External 4) Internal Question No: 45 (Marks: 1) - Please choose one The interval from the time of submission to the time of completion is the. 1) Turnaround time (Page#83) 2) Waiting time 3) Response time 4) None of all these Question No: 46 (Marks: 1) - Please choose one Consider a scenario of CPU protection, is added to the operating system in order to detect and avoid loop in a user program. 1) I/O 2) Timer (Page#11) 3) Base and limit registers 4) Turning interrupt enable off Question No: 47 (Marks: 1) A time sharing system is: - Please choose one 1) Multi tasking 2) Interactive 3) Multi user 4) All of these (Page#9)

13 Question No: 48 (Marks: 1) - Please choose one threads are supported directly by the operating system. 1) Kernel (Page#73) 2) Functional 3) Non-functional 4) User Question No: 49 (Marks: 1) - Please choose one Each process must first request permission to enter its critical section. The section of code implementing this request is called the. 1) Entry section (Page#100) 2) Critical Section 3) Remainder section 4) None of all these Question No: 50 (Marks: 1) - Please choose one A can be thought of as a program in execution. 1) Process (Page#28) 2) Files 3) System 4) All of the these Question No: 51 (Marks: 1) - Please choose one A Process that has finished working, as well as its parent process has also finished its execution. In this state the process A will be called as process. 1) Child (Page#35) 2) Thread 3) Zombie 4) Fork

14 Question No: 52 (Marks: 1) - Please choose one Shared libraries and kernel modules are stored in director. 1) /bin 2) /dev 3) /boot 4) /lib (Page#23) Question No: 53 (Marks: 1) - Please choose one The bottom layer in the layered approach of Operating System is. 1) User interface 2) Hardware (Page#21) 3) Kernel 4) None of the given options Question No: 54 (Marks: 1) - Please choose one Each process is represented in the operating system by: 1) Process control block (Page#30) 2) Process state 3) CPU Scheduling information 4) Program counter Question No: 55 (Marks: 1) - Please choose one In addressing, the recipient is not required to name the sender. 1) Symmetric 2) Asymmetric (Page#47) 3) Both symmetric and asymmetric 4) None of the given options Question No: 56 (Marks: 1) - Please choose one The performance of Round Robin algorithm does NOT depends heavily on the size of the time quantum. 1) True (Page#89) 2) False

15 Question No: 57 (Marks: 1) - Please choose one Switching the CPU from one process to another requires saving of the context of the current process and loading the state of the new process is called: 1) Context switching (Page#31) 2) Process Scheduling 3) Process control block 4) None Question No: 58 (Marks: 1) - Please choose one I MB or 1 megabyte is equivalent to bytes bytes bytes bytes Question No: 59 (Marks: 1) - Please choose one In model, there is a kernel thread for every user thread. 1) One-to-one (Page#74) 2) Many to-one 3) One-to-many 4) Many-to-many Question No: 60 (Marks: 1) - Please choose one The creating process is called a process while the new processes are called the of that process. 1) Parent, children (Page#38) 2) Children, parent 3) Zombie, single 4) None of the given options

16 Question No: 61 (Marks: 1) - Please choose one provides a mechanism to allow processes to communicate and to synchronize their actions without sharing the same address space. Process synchronization Inter-process Communication Message Passing System Direct Communication (Page#43) Question No: 62 (Marks: 1) - Please choose one The integer value of semaphores can not be greater than 1. Counting Binary (Page#117) Mutex Bounded buffer Question No: 63 (Marks: 1) - Please choose one scheduler takes the process from the ready queue and assign the CPU with the help of Dispatcher. Long term (Page#83) Short term Medium term Swapper Question No: 64 (Marks: 1) - Please choose one A solution to the critical section problem must satisfy the following requirements Progress Mutual exclusion Bounded Waiting All of these (Page#101)

17 Question No: 65 (Marks: 1) - Please choose one In buffering, queue can be implemented in how many ways? (Page#44) 4 Question No: 66 (Marks: 1) - Please choose one First-Come, First-Served (FCFS) is a scheduling algorithm. Preemptive Non-preemptive (Page#83) Both preemptive and non- preemptive None of the given options Question No: 67 (Marks: 1) - Please choose one While two processes in execution, only one can be in critical section at a time, this requirement is named as. Race condition Mutual exclusion (Page#101) Progress Bounded waiting Question No: 68 (Marks: 1) - Please choose one The time it takes for the dispatcher to stop one process and start another running is known as the. Dispatch latency Scheduling Context switching None (Page#82)

18 Question No: 69 (Marks: 1) - Please choose one is used to request the OS by the process to take an I/O or initiating child process. System call Interrupt Trap Signal (Page#196) Question No: 70 (Marks: 1) - Please choose one You can display all of the signals supported by your system, along with their numbers, by using the command: <Ctrl-A> fg jobs kill -l (Page#69) Question No: 71 (Marks: 1) - Please choose one are used for communication between related or unrelated processes on a UNIX/Linux system. Pipe BSD Socket Named pipe (FIFO) (Page#49) All Question No: 71 (Marks: 1) - Please choose one The major advantage of multi-programming system is: More than one jobs can be processed at a given time CPU utilization can be increased (Page#8) Jobs can be completed quickly All of the options are correct

19 Question No: 71 (Marks: 1) - Please choose one are supported above kernel and are implemented by a thread library. User level threads (Page#70) Kernel threads Both kernel and user level thread None of the given option Question No: 72 (Marks: 1) - Please choose one A semaphore that cause Busy-Waiting is termed as: Monitor Critical region Critical section Spinlock (Page#112) Question No: 73 (Marks: 1) - Please choose one Consider three processes in scheduling. Here are the waiting times for the three processes P1 = 4; P=2; P3 = 6. Which one of the following is correct average waiting time per process? Question No: 74 (Marks: 1) - Please choose one IPC provides a mechanism to allow processes to communicate and to synchronize their actions without sharing the same Address space (Page#46) Address Name Address ID None of all these

20 Question No: 75 (Marks: 1) - Please choose one is a kernel module that takes control of the CPU from the current process and gives it to the process selected by the short-term scheduler. CPU Scheduler Dispatcher (Page#79) Scheduling Criteria Scheduling Algorithm Question No: 76 (Marks: 1) - Please choose one The requires that once a writer is ready, that writer performs its write as soon as possible, if a writer waiting to access the object, no new readers may start reading. first readers-writers problem second readers-writers problem third readers-writers problem fourth readers-writers problem (Page#119) Question No: 77 (Marks: 1) The scheduling criteria include: - Please choose one CPU utilization Throughput Turnaround time All of these (Page#80) Question No: 78 (Marks: 1) A binary semaphore. - Please choose one has the values one or zero (Page#117) is essential to binary computers is a deadlock scheme is a preemption scheme

21 Question No: 79 (Marks: 1) - Please choose one A process produces information that is consumed by a process. 1. Consumer, Producer 2. Producer, Consumer (Page#44) 3. Customer, Purchaser 4. Merchandiser, Consumer Question No: 80 (Marks: 1) - Please choose one The algorithm may either be preemptive or non-preemptive. 1. Round-Robin 2. Sorted Job First (SJF) (Page#82) 3. Priority Scheduling 4. All of the given options Question No: 81 (Marks: 1) - Please choose one Binary semaphores are those that have only two values. 0 and n 0 and 0 0 and 1 (Page#117) None of the given options Question No: 82 (Marks: 1) - Please choose one In this which formula is called the Little s formula? n = λ * W n = λ n = W n = W * λ (Page#93)

22 Question No: 83 (Marks: 1) - Please choose one Blocking is considered and Non-blocking is considered. 1. Synchronous, Asynchronous (Page#47) 2. Synchronous, Asynchronous 3. Direct, Indirect 4. Zero capacity, Bounded capacity Question No: 84 (Marks: 1) - Please choose one The section of code after the critical section is called. 1. Crystal section 2. Entry section (Page#99) 3. Remainder section 4. Exit section Question No: 85 (Marks: 1) - Please choose one The correct command for compiling C program named program.c in Linux environment is: 1. gcc program.c o FirstPrgram (Page#31) 2. gcc o FirstProgram program.c 3. gcc z FirstProgram program.c 4. gcc program.c m FirstPrgram Question No: 86 (Marks: 1) - Please choose one involve programming a model of the computer system, in order to get a more accurate evaluation of the scheduling algorithms. 1. Analytic Evaluation 2. Implementation 3. Simulations (Page#93) 4. All

23 Question No: 87 (Marks: 1) - Please choose one Critical section problem can be solved by using how many ways? 4 3 (Page#98) 1 2 Question No: 88 (Marks: 1) - Please choose one commands in Linux is used to copy file 1. is 2. cp (Page#30) 3. mv 4. mkdir Question No: 89 (Marks: 1) - Please choose one are used by shell commands to pass data from one shell pipeline to another, without creating temporary files. 1. Pipes 2. Message queues 3. BSD sockets 4. FIFOs (Page#61) Question No: 90 (Marks: 1) - Please choose one Time interval when the I/O Devices are accessed is known as. 1. CPU Burst 2. IO Burst (Page#78) 3. Time Slice 4. None of Above

24 Question No: 91 (Marks: 1) mkfifo() is a (an). - Please choose one 1. System call 2. Library call (Page#58) 3. Interrupt 4. Signal Question No: 92 (Marks: 1) - Please choose one The Shortest-Job-First Scheduling algorithm can be: 1. Preemptive only 2. Non-preemptive only 3. Preemptive or Non-preemptive (Page#85) 4. None of the given options Question No: 93 (Marks: 1) - Please choose one In producer-consumer problem synchronization is required. On which shared area this synchronization actually affect? 1. Counter 2. Buffer (Page#41) 3. Entry section 4. Exit section Question No: 94 (Marks: 1) - Please choose one A is an abstract key for accessing a file. 1. File descriptor (Page#46) 2. Input Redirection 3. Output Redirection 4. FIFO

25 Question No: 95 (Marks: 1) - Please choose one A is a multi-user, multi-process, and interactive system. 1. Batch systems 2. Single-user system 3. Time-sharing systems (Page#9) 4. Multi programmed systems Question No: 96 (Marks: 1) - Please choose one The are used for communication between related or unrelated processes on the same system or unrelated processes on different systems. 1. Pipes 2. BSD Sockets (Page#53) 3. Named pipe (FIFO) 4. None of the given options Question No: 97 (Marks: 1) - Please choose one Consider a system of N processes (Po,P1_Pn-1). Each process in its critical section and the process may be changing common variables, updating a table, writing a file etc. No other process is allowed to execute in its critical section. This problem is called. 1. Bakery algorithm 2. N-Mutual exclusion 3. N-Process Critical Section (Page#103) 4. Deadlock algorithm Question No: 98 (Marks: 1) - Please choose one Round Robin algorithm is similar to scheduling but preemption is added to switch between processes. 1. Shortest job first 2. Shortest Remaining Time First 3. First Come First Server (Page#88) 4. None of these

26 Question No: 99 (Marks: 1) - Please choose one Keep in mind scheduling algorithm, when you go to any famous fast food franchise.on entering the store, each customer receives a number. The customer with the lowest number is served next. This algorithm is called. Dijkastra algorithm Simple algorithm Deadlock algorithm Bakery algorithm (Page#103) Question No: 100 (Marks: 1) - Please choose one Banker s algorithm is used for. Deadlock avoidance Deadlock detection Deadlock prevention Deadlock removal (Page#140) Question No: 101 (Marks: 1) - Please choose one is an integer variable accessible through wait and signal which are atomic operations. Semaphore Mutex Busy waiting Signal (Page#111) Question No: 102 (Marks: 1) - Please choose one The priorities of processes in the Group remain fixed whereas the priorities of processes in the Group are recalculated every second. Kernel, Kernel User, Kernel User, User Kernel, User (Page#93)

27 Question No: 103 (Marks: 1) - Please choose one When a process P1 switches from the running state to the waiting state because an I/O request is being completed.this scheduling is called. Non-Preemptive Switching Termination Preemptive (Page#80) Question No: 104 (Marks: 1) - Please choose one A system call. Allows a program to request a kernel service Is a technique to protect I/O devices and other system resources Is an entry point into the kernel code (Page#18) All of the these Question No: 105 (Marks: 1) - Please choose one All within a process share the same address space Threads (Page#70) Processes CPU burst IO Burst Question No: 106 (Marks: 1) - Please choose one The condition where a set of blocked processes each holding a resource and waiting to acquire a resource held by another process in the set, is termed as. Deadlock (Page#130) Starvation Both of the above options None of these

28 Question No: 107 (Marks: 1) - Please choose one buffer places no practical limit on the size of the buffer Bounded Unbounded (Page#44) Both Unbounded & bounded None of the given options Question No: 108 (Marks: 1) - Please choose one Using hardware solution to synchronization for complex problems, introduce a new synchronization tool know as. TestAndSet Semaphore Swap Trap (Page#111) Question No: 107 (Marks: 1) - Please choose one has a hierarchical file system structure. DOS Windows UNIX (Page#25) None of the given options Question No: 108 (Marks: 1) - Please choose one You can use the command in UNIX to create a directory. rmdir mkdir cp gcc (Page#29)

29 Question No: 109 (Marks: 1) - Please choose one In instruction TestAndSet mutual exclusion implementation is done by declaring a Boolean variable lock. Initialized as zero Initialized as true Initialized as 1 Initialized as false (Page#109) Question No: 110 (Marks: 1) - Please choose one The process id returned to the child process after successful fork system call execution is. 0 (Page#40) Question No: 111 (Marks: 1) - Please choose one A is a multi-user, multi-process, and interactive system Batch systems Single-user system Time-sharing systems (Page#9) Multi programmed systems Question No: 112 (Marks: 1) - Please choose one DOS is single user operating system. True (Page#7) False Question No: 113 (Marks: 1) - Please choose one You can create a threads by using the pthread_create() call. True False (Page#76)

30 Question No: 114 (Marks: 1) - Please choose one Use of semaphore create a problem of busy waiting, this wastes CPU cycles that some other process may be able to use productively. This type of semaphore is also called. Semaphore S Spinlock (Page#112) Locking Semaphore Mutex Question No: 115 (Marks: 1) - Please choose one register contains the size of the process Base register Index register Limit register (Page#13) Stack pointers register Question No: 116 (Marks: 1) - Please choose one The priorities of processes in Group remain fixed whereas the priorities of processes in the Group are recalculated every second. Kernel, Kernel User, Kernel User, User Kernel, User (Page#93) Question No: 117 (Marks: 1) - Please choose one Current working directory can be accessed using Command.. (dot) # ( hash ) / (slash) ~ (tilt) (Page#25)

31 Question No: 118 (Marks: 1) - Please choose one Preemptive scheme of Short job first scheduling is known as. First Come First Serve Scheduling Priority Scheduling Round-Robin Scheduling Shortest-Remaining-Time-First (Page#85) Question No: 119 (Marks: 1) - Please choose one In communication the process which wants to communicate with the other process must explicitly name the recipient and the sender. Direct (Page#46) Indirect Automatic Self Question No: 120 (Marks: 1) - Please choose one Removing the possibility of deadlock in dining philosopher problem does not ensure the problem will not occur. Mutual Exclusion Starvation (Page#123) Critical Section Bounded Buffer Question No: 121 (Marks: 1) - Please choose one Command-line interpreter is also called in some operating systems. Kernel Shell Signal API (Page#16)

32 Question No: 122 (Marks: 1) - Please choose one In producer-consumer problem synchronization is required. On which shared area this synchronization actually affect? Counter Buffer (Page#45) Entry section Exit section Question No: 123 (Marks: 1) - Please choose one The Purpose of Operating System is to generate Executable Programs and to them. Regenetrate Execute (Page#5) Store Remove Question No: 124 (Marks: 1) - Please choose one Process synchronization is a process of helping processes to. update the shared data simultaneously update the shared data and resources in an orderly fashion not to update the shared data or memory access data and memory at first come first serve basis (Page#98) Question No: 125 (Marks: 1) - Please choose one You can use the rm file1 command to file1 Retrieve Remove Make modify (Page#30)

33 Question No: 126 (Marks: 1) - Please choose one is a segment of code that accesses a shared resource like data structure or device that must not be concurrently accessed by more than one thread of execution. Multithreading Context switching Critical section Pipelining (Page#105) Question No: 127 (Marks: 1) - Please choose one Which of the following is correct definition for wait operation? wait(s) { while(s<=0) ;// no o S--; } (Page#111) wait(s) { S++; } wait(s) { while(s>=0) ;// no op S--; } wait(s) { S--; } Question No: 128 (Marks: 1) - Please choose one All within a process share the same address space. Threads Processes CPU burst IO Burst (Page#70)

34 Question No: 129 (Marks: 1) - Please choose one While executing the statement c++/c-- in Producer-Consumer problem, at back end certain number of instructions are executed, if interleaving of statements happen, it create race condition. Tell number of instructions that require no interleaving while executing c++/c--? Question No: 130 (Marks: 1) - Please choose one In deadlock detection and recovery algorithm, a deadlock exists in the system if and only if the wait for graph contains a. Cycle Graph Edge Node (Page#147) Question No: 131 (Marks: 1) - Please choose one provides basic computing resources. Application programs Operating System Hardware (Page#4) Users Question No: 132 (Marks: 1) - Please choose one Physical memory is broken down into fixed-sized blocks, called and Logical memory is divided into blocks of the same size, called. Frames, pages (Page#165) Pages, Frames Frames, holes Holes, segments

35 Question No: 133 (Marks: 1) - Please choose one Critical section problem can be solved by using how many ways? 4 (Page#98) 1 2 Question No: 134 (Marks: 1) - Please choose one Using system, we can create a new process in Linux. fork (Page#39) exec wait exit Question No: 135 (Marks: 1) - Please choose one The systems that control scientific experiments, medical imaging systems, industrial control systems and certain display systems are examples of systems. Real Time system Batch Multi programmed Time-sharing system (Page#9) Question No: 136 (Marks: 1) - Please choose one If the system can allocate resources to each process in some order and still avoid a deadlock then it said to be in state. Safe (Page#137) Unsafe Mutual Starvation

36 Question No: 137 (Marks: 1) - Please choose one Consider three processes in scheduling. Here are the waiting times for the three processes P1 = 4; P=2; P3 = 6. Which one of the following is correct average waiting time per process? (Page#82) Question No: 138 (Marks: 1) - Please choose one The process of holding at least one resource and waiting to acquire additional resources that are currently being held by other processes is known as. Mutual exclusion Hold and wait No preemption Circular wait (Page#131) Question No: 139 (Marks: 1) - Please choose one A named pipe is a pipe whose access point is a file kept on the file system called as. Named FIFO FIFO (Page#45) All of the above given options None of the given Question No: 140 (Marks: 1) - Please choose one is a preemptive scheduling algorithm. First Come First Serve Shortest Job First Round Robin (Page#89) None of these

37 Question No: 141 (Marks: 1) - Please choose one Clock interrupt handler is an example of kernel thread that is not executed for servicing a request by a user thread. It is named as. EINVAL EAGAIN LWP POSIX (Page#73) Question No: 142 (Marks: 1) - Please choose one Database, Complier, Video games are examples of. Hardware Application (Page#4) Operating System Users Question No: 143 (Marks: 1) - Please choose one No resource can be forcibly removed from a process holding it best describes which one of the following conditions? Mutual Exclusion Hold and wait Starvation No preemption (Page#131) Question No: 144 (Marks: 1) - Please choose one determines How to do something. Mechanism (Page#24) Policy Mechanism and Policy None of the given

38 Question No: 145 (Marks: 1) - Please choose one scheduling algorithm can be preemptive or non-preemptive. First Come First Serve Shortest Job First (Page#83) Round Robin Priority Question No: 146 (Marks: 1) - Please choose one The scheme is not applicable to a resource allocation system with multiple instances of each resource type. Wait for graph (Page#148) Resource allocation graph Both Resource-allocation and wait-for graph None of the given options Question No: 147 (Marks: 1) - Please choose one threads are implemented by a thread library at the user level. Kernel User (Page#73) Functional Non-functional Question No: 148 (Marks: 1) - Please choose one What do we name to an address that is loaded into the memory-address register of the memory? Logical address Physical address (Page#155) Binary addresses None of the given options

39 Question No: 149 (Marks: 1) - Please choose one algorithm is used for solving n-process critical section problem. Bankers Bakery (Page#103) Babbles None of the given Question No: 150 (Marks: 1) - Please choose one algorithm is used in Deadlock avoidance. Bakery Banker s (Page#139) Mutual exclusion Safe Sequence Question No: 151 (Marks: 1) - Please choose one The wait () system call suspends the calling process until one of the immediate children or until a child that is being traced stops because it has hit an event of interest. Processes Terminates Sleeps Executes (Page#42) Question No: 152 (Marks: 1) - Please choose one Each page is a power of bytes long in paging scheme (Page#167)

40 Question No: 153 (Marks: 1) - Please choose one Blocking is considered and Non-blocking is considered. Synchronous, Asynchronous Synchronous, Asynchronous Direct, Indirect Zero capacity, Bounded capacity (Page#47) Question No: 154 (Marks: 1) - Please choose one Each page is a power of bytes long in paging scheme (Page#167) Question No: 155 (Marks: 1) - Please choose one In client-server applications, which of the following are used to pass data between a server process and client processes? FIFOs (Page#61) Message queues BSD sockets Pipes Question No: 156 (Marks: 1) - Please choose one command gives a snapshot of the current processes. ps top who ls (Page#66)

41 Question No: 157 (Marks: 1) - Please choose one is a software based solution to the synchronization problem. Bakery algorithm TSL instruction Semaphore (Page#111) Monitors Question No: 158 (Marks: 1) - Please choose one The semaphore provides mutual exclusion for accesses to the buffer pool and is initialized to the value 1. mutex (Page#118) binary couting none of the given options Question No: 159 (Marks: 1) - Please choose one In a Multilevel Queue, the foreground queue has scheduling algorithm and background queue has scheduling algorithm First Come First Serve, Round-Robin Round-Robin, First Come First Serve (Page#91) Round-Robin, Round-Robin First Come First Serve, First Come First Serve Question No: 160 (Marks: 1) - Please choose one The address generated by the CPU, after any indexing or other addressing-mode arithmetic, is called a address, and the address it gets translated to by the MMU is called a address. Virtual, physical (Page#153) Hexadecimal, Binary Valid, invalid Physical, Virtual

42 Question No: 161 (Marks: 1) - Please choose one Time from submission to completion of process is called. Response Time (Page#83) Throughput Waiting Time Turnaround Time: Question No: 162 (Marks: 1) - Please choose one scheduling allows a process to move between queues. Round Robin First Come First Serve Multilevel Feedback Queue Shortest Remaining Time First (Page#92) Question No: 163 (Marks: 1) - Please choose one Which type of operating system guarantees that critical tasks must be completed on time? Timesharing system Multitasking system Batch system Realtime system (Page#10) Question No: 164 (Marks: 1) - Please choose one Which of the Following is not an Operating System. Linux Unix Windows Xp Datebase (Page#7)

43 Question No: 165 (Marks: 1) - Please choose one In a multithreaded model, which one of the following provides true concurrency? Many-to-one One-to-one (Page#74) Many-to-many One-to-many Question No: 166 (Marks: 1) - Please choose one In Layered approach of OS, Lowest Layer is known as. Software Layer Hardware Layer Lower Level Layer None of The Given (Page#21) Question No: 165 (Marks: 1) - Please choose one Which of the following is used to show the end of file in unix? Ctrl+D Ctrl+A Ctrl+O Ctrl+E Question No: 165 (Marks: 1) - Please choose one In Resource Allocation Graph, A Pi Rj indicates that process Pi may request resource Rj at some time in the future. Claim edge (Page#138) Request edge Assignment edge Allocation edge

44 Question No: 169 (Marks: 1) - Please choose one and CPU registers are specifically designed to provide memory protection by limiting access to a process with in its address space. Counter, add Base, limit (Page#13) Program counter, accumulator Buffer, data register Question No: 170 (Marks: 1) - Please choose one The critical section problem can be solved by the following except: Software based solution Firmware based solution (Page#101) Operating system based solution Hardware based solution Question No: 171 (Marks: 1) - Please choose one Mach, MacOS X Server, QNX, OS/2 and Windows NT are examples of OS Based on. Layered Micro Kernal (Page#22) Virtual Machine None of The Given Question No: 172 (Marks: 1) - Please choose one A time interval when a process uses I/O devices only is called. CPU burst I/O burst (Page#78) Scheduling Context switching

45 Question No: 173 (Marks: 1) - Please choose one Under scheduling, once the CPU has been allocated to a process, the process keeps the CPU until either it switches to the waiting state, finishes its CPU burst, or terminates. Short-term scheduler Preemptive Non-preemptive (Page#82) Both preemptive and non- preemptive Question No: 174 (Marks: 1) - Please choose one Which register holds the smallest legal physical memory address for a process? Base register (Page#13) Limit register Status register None of the given options Question No: 175 (Marks: 1) - Please choose one The non-critical section code in any critical section problem is termed as. Critical Section Entry Section Leave/Exit Section Remainder Section (Page#101) Question No: 176 (Marks: 1) - Please choose one directory includes essential system boot files including the kernel image. /bin /boot /dev /etc (Page#26) Question No: 177 (Marks: 1) - Please choose one Cache is non-volatile memory. True False (Page#153)

46 Question No: 178 (Marks: 1) - Please choose one In direct communication, link is associated with exactly pair(s) of communicating processes. Four Two (Page#47) One Three Question No: 179 (Marks: 1) - Please choose one You can use the mv file1 file2 command to move file1 to file2 (Page#30) file 2 to file 1 this command will not work for moving files None of the given options Question No: 180 (Marks: 1) - Please choose one In Unix/Linux client server process communication, server process runs in the background by terminating its command line with. % $ (Page#65) Question No: 181 (Marks: 1) - Please choose one I/O instructions are Privileged Instructions. True False (Page#12) Question No: 182 (Marks: 1) - Please choose one The basic purpose of is to help the users to utilize the hardware resources for completing different tasks in a simplified manner Operating system Application software All Software All of the given (Page#6)

47 Question No: 183 (Marks: 1) - Please choose one Linux OS can support multiple users at a time True False (Page#9) Question No: 184 (Marks: 1) - Please choose one Preemptive scheduling is sometimes called shortest-remaining-time-first scheduling. First-Come-First-Served (FCFS) Round-Robin Sorted Job First (SJF) (Page#85) Priority Question No: 185 (Marks: 1) - Please choose one The execution of critical sections must NOT be mutually exclusive. True False (Page#100) Question No: 186 (Marks: 1) - Please choose one OS helps manages the following except: Application software Bus speed of the system Memory Virtual memory Question No: 187 (Marks: 1) - Please choose one In Layered Approach of OS, the Layer highest Layer is User Interface layer. True False (Page#21) Question No: 188 (Marks: 1) - Please choose one User mode can run the Privileged instructions. 1 0 (Page#11)

48 CS604 Operating System Quizzes MCQ s 1) Each thread has its own. Process ID (PID) Address space Thread ID (TID) Open file descriptors (Page#70) 2) You can compile yours program in a UNIX/LINUX system by the command. $rm $cp $mv Gcc (Page#31) 3) A process terminates by calling the system call. Wait Fork exec exit (Page#39) 4) Semaphore can be used for solving. Wait & signal Deadlock Synchronization Priority (Page#111)

49 5) The process that satisfies all three requirements of critical section problem is called. Algorithm 1 Algorithm 2 Algorithm 3 Algorithm N (Page#104) 6) A page table needed for keeping track of pages of the page table is called. 2-level paging Page directory (Page#173) Page size Page table size 7) Kernel is responsible for scheduling the user level threads. True False (Page#73) 8) Swapper is also termed as Short term scheduler. True False (Page#36) 9) A major problem with priority scheduling algorithms is. Deadlock Aging Starvation None of these (Page#86) 10) Progress and Bounded Waiting are some of the characteristics to solve the critical section problems. True False (Page#101)

50 11) A process is a process that has terminated but whose exit status has not yet been received by its parent process or by init. Parent Zombie Child Fork (Page#42) 12) A process is said to be in critical section if it executes code that manipulates shared data True False (Page#100) 13) A parent process calling system call will be suspended until children process terminates. wait fork exit exec (Page#39) 14) An absolute pathname starts with the root directory (/) and a relative pathname starts with your home directory. True False (Page#25) 15) The TSL (TestAndSet instruction) which is the hardware solution to synchronization problem does not satisfy the condition, hence not considered to be a good solution. Progress Bounded waiting Mutual exclusion No preemption (Page#109)

51 16) In, user does not get to interact with his/her jobs and jobs having similar needs are executed in groups at the same time, one after the other. Batch systems (Page#7) Multi programmed systems Single-user system Time-sharing systems 17) Operating System is the Manager of Hardware Resources. True (Page#6) False 18) A dashed line is used to represent a in Resource Allocation Graph. Claim edge (Page#138) Request edge Assignment edge Allocation edge 19) If a system is not in a safe state, there can be No deadlocks. True False (Page#137) 20) The following is NOT a classical problem of synchronization: Bounded buffer problem Reader writer problem Dining philosopher s problem Counting semaphore problem (Page#118) 21) User Goal of OS is that It easy to use, reliable, safe and fast. True False (Page#24)

52 22) The condition in which a set {P0, P1 Pn} of waiting processes must exist such that P0 is waiting for a resource that is held by P1, P1 is waiting for a resource that is held by P2, and so on, Pn-1 is waiting for a resource held by Pn, and Pn is waiting for a resource held by P0. This condition is known as. Mutual exclusion Hold and wait No preemption Circular wait (Page#131) 23) We can install and run multiple OS by using VMWare. True False (Page#20) 24) A, (or an exception) is a software-generated interrupt caused either by an error (division by zero or invalid memory access) or by a user request for an operating system service. Interrupt Trap Signal Process (Page#10) 25) Cooperating processes never share any data, code, memory or state. True False (Page#5) 26) In Unix/ Linux, by default the standard input file is attached to the Mouse Keyboard Light pen Joystick (Page#55)

53 27) A time interval when a process uses CPU only is called. Scheduling I/O burst CPU burst (Page#78) Dispatch latency 28) The process of switching from one process to another is called latency. True False (Page#34) 29) Which of the following is NOT a Hardware Resource? CPU OS (Page#4) I/O Devices Memory 30) An operating system is a control program that manages the execution of user programs to prevent errors and improper use of a computer. True False (Page#6) 31) The integer value of semaphores can range over an unrestricted integer domain. Counting (Page#117) Binary Mutex Bounded buffer

54 32) In model, many user-level threads are supported per kernel thread. One-to-one Many to-one Many-to-many One-to-many (Page#73) 33) Linux Treats Devices as Files. True False (Page#26) 34) A condition where a set of blocked processes each holding a resource and waiting to acquire a resource held by another process in the set is termed as. Deadlock (Page#130) Starvation Both of the above None of the given options 35) The Swap instruction which is the hardware solution to synchronization problem does not satisfy the condition, hence not considered to be a good solution. Progress Bounded waiting Mutual exclusion No preemption (Page#109) 36) A program in execution is called a. Command Process Software Compiler (Page#31)

55 37) Round Robin algorithm is most suitable for. Time sharing system (Page#88) Real time systems and batch systems Running Batch programs Expert system 38) Hardware provides basic computing resource. True False (Page#4) 39) Please choose one copy file1 file2 is an example of OS view. Top down (Page#6) Bottom Up Both of these None of the given options 40) /opt is used for storage of large applications. True False (Page#27) 41) The manual pages can be read in Linux using command. man wan desc help (Page#27) 42) The Top-down view is that it is a program that acts as an intermediary between a user of a computer and the computer hardware, and makes the computer system convenient to use. True False (Page#6)

56 43) is a solution to the problem of indefinite blockage of low-priority processes. Starvation Deadlock Aging (Page#87) None of these 44) Users are the People, machines or computers that uses the Hardware resources. True False (Page#4) 45) The nice value helps in assigning to a process. Priority (Page#94) Weight Time Scheduling 46) Operating system enables the user to use the Hardware Resources. True False (Page#4) 47) system call is used to write to a file or FIFO or any other IPC channel. read write open fork (Page#48) 48) The bottom-up view is that operating system is a resource manager who manages the hardware and software resources in the computer system. True False (Page#6)

57 49) A Process A that has finished working but its parent process has also finished its execution. In this state the process A will be called as process. Child Thread Zombie (Page#42) Fork 50) The priorities of processes in the group remain fixed. Kernel (Page#93) User Kernel & User None of these 51) command display the status of a process. ls ps gcc cat (Page#66) 52) integer shows the highest priority of a process in CPU scheduling. Small (Page#86) Large Both of these All of the given options 53) You can display the contents (names of files and directories) of a directory in UNIX/Linux directory structure with the command. ll s ls (Page#28) none of the given options

58 54) In Linux directory structure, there is root directory. 1 (Page#26) ) is a virtual directory in Linux and Unix. /proc /temp /boot /ver (Page#27) 56) The system call suspends the calling process. fork wait exec exit (Page#42) 57) is a piece of code in a cooperating process in which the process may updates shared data (variable, file, database, etc.). Critical analysis Critical section Critical path Critical code (Page#100) 58) In Unix/ Linux, by default the standard output file is attached to the. File Screen Printer Scanner (Page#59)

59 59) When process opens its first file explicitly it will get descriptor number (Page#50) 4 60) rm and [r]mkdir commands are used to directory. Create Move Remove Modify (Page#30) 61) is also called Swapper. Swap space Medium term scheduler Short term scheduler Long term scheduler (Page#37) 62) Shared libraries and kernel modules are stored in directory /bin /dev /boot /lib (Page#26) 63) Utilities used for system administration (halt, ifconfig, fdisk, etc.) are stored in directory. /dev /boot /lib /sbin (Page#27)

60 64) The scheduling of are done by the operating system. Kernel threads (Page#73) User level threads Both kernel and user level thread None of the give option 65) is the basis of queuing theory which is branch of mathematics used to analyze systems involving queues and servers. Little s Formula (Page#96) Deterministic modeling Queuing Theory Queuing Analysis 66) The number of processes completed per unit time is called. Turn around time Throughput (Page#83) Response time Dispatch latency 67) You can terminate a foreground process by pressing. <Ctrl-A> <Ctrl-C> (Page#69) <Ctrl-Z> None of the given options 68) If the fork system call fails, it returns: 1-1 (Page#40) 2 0

61 69) The following requirement for solving critical section problem is known as. There exists a bound on the number of times that other processes are allowed to enter their critical sections after a process has made a request to enter its critical section and before that request is granted. Progress Bounded Waiting Mutual Exclusion Critical Region (Page#101) 70) Bounded Buffer is a buffer of size. variable fixed (Page#44) both of these none of the given options 71) displays information about the top processes. Is Cs Top Cd (Page#67) 72) A process consists of. One or more threads Code Data All of the given (Page#12)

62 73) You can use the command to display the status of suspended and background processes fg bg jobs kill (Page#68) 74) Linux uses directory to store system configuration files. /bin /dev /boot /etc (Page#26) 75) The procedure The time at which the process finished working MINUS the arrival time of the process MINUS CPU burst for that process will help calculate the. On-Preemptive Shortest Job First scheduling. Preemptive Shortest Job First scheduling FCFS RR Scheduling (Page#85) 76) If your processor does not have two slots empty in Per Process File Descriptor Table, then your system call will fail. Pipe read write open (Page#55)

63 77) A pathname is the list of directories separated by. # $ & / (Page#25) 78) The priority of a process can be changed using command. nice cmd cat grep (Page#94) 79) First entries in Per Process File Descriptor Table are used as soon as the process is created (Page#54) 80) All threads within a process share the address space. Same Different (Page#71) Both of the above None of the given options

64 81) Choose one command displays the contents of current working directory. Is (Page#28) Cs Mv All of given 82) Batch programs are usually programs. Interactive Non-interactive (Page#5) Foreground Preemptive Best of Luck