Quiz Sail Part 2 Flashcards by Ernesto Gastelum

Access matrix model for user authentication contains:
A: a list of objects
B: a function which returns an object’s type
C: a list of domains
D: all of the mentioned

D: all of the mentioned

How well did you know this?

Not at all

Perfectly

In the single level directory:
A: all of the mentioned
B: all files must have unique names
C: all files must have unique owners
D: all directories must have unique names

B: all files must have unique names

How well did you know this?

Not at all

Perfectly

A parent process calling –?– system call will be suspended until children processes terminate.
A: fork
B: exit
C: wait
D: exec

C: wait

How well did you know this?

Not at all

Perfectly

In a system that does not support swapping:
A: binding of symbolic addresses to physical addresses normally takes place during execution
B: the compiler normally binds symbolic addresses (variables) to relocatable addresses
C: the loader binds relocatable addresses to physical addresses
D: the compiler normally binds symbolic addresses to physical addresses

B: the compiler normally binds symbolic addresses (variables) to relocatable addresses

How well did you know this?

Not at all

Perfectly

What is breach of availability?
A: This violation involves unauthorized use of resources
B: This violation involves unauthorized destruction of data
C: This violation involves unauthorized modification of data
D: This type of violation involves unauthorized reading of data

B: This violation involves unauthorized destruction of data

How well did you know this?

Not at all

Perfectly

To differentiate the many network services a system supports –?– are used.
A: Variables
B: Service names
C: Sockets
D: Ports

D: Ports

How well did you know this?

Not at all

Perfectly

Spinlocks are:
A: Locks that avoid time wastage in context switches
B: CPU cycles wasting locks over critical sections of programs
C: Locks that work better on multiprocessor systems
D: All of the mentioned

D: All of the mentioned

How well did you know this?

Not at all

Perfectly

The code segment that misuses its environment is called a:
A: code stacker
B: trojan horse
C: internal thief
D: none of the mentioned

B: trojan horse

How well did you know this?

Not at all

Perfectly

The circular wait condition can be prevented by:
A: using thread
B: defining a linear ordering of resource types
C: all of the mentioned
D: using pipes

B: defining a linear ordering of resource types

How well did you know this?

Not at all

Perfectly

The idea of overlays is to:
A: all of the mentioned
B: data that are needed at any given time
C: enable a process to be larger than the amount of memory allocated to it
D: keep in memory only those instructions

A: all of the mentioned

How well did you know this?

Not at all

Perfectly

External fragmentation exists when:
A: a request cannot be satisfied even when the total memory is free
B: none of the mentioned
C: the total memory is insufficient to satisfy a request
D: enough total memory exists to satisfy a request but it is not contiguous

D: enough total memory exists to satisfy a request but it is not contiguous

How well did you know this?

Not at all

Perfectly

The usefulness of signals as a general inter process communication mechanism is limited because:
A: none of the mentioned
B: they cannot carry information directly
C: they do not work between processes
D: they are user generated

B: they cannot carry information directly

How well did you know this?

Not at all

Perfectly

Error handler codes, to handle unusual errors are:
A: almost never executed
B: executed very often
C: none of the mentioned
D: executed periodically

A: almost never executed

How well did you know this?

Not at all

Perfectly

A file is a/an –?– data type.
A: abstract
B: private
C: primitive

A: abstract

How well did you know this?

Not at all

Perfectly

The current directory contains, most of the files that are:
A: of current interest to the user
B: not of current interest to the system
C: not used in the system
D: stored currently in the system

A: of current interest to the user

How well did you know this?

Not at all

Perfectly

The –?– keeps state information about the use of I/O components.
A: OS
B: CPU
C: shell
D: kernel

D: kernel

How well did you know this?

Not at all

Perfectly

In a time-sharing operating system, when the time slot given to a process is completed, the process goes from the running state to the:
A: Blocked state
B: Terminated state
C: Suspended state
D: Ready state

D: Ready state

How well did you know this?

Not at all

Perfectly

When an attempt is to make a machine or network resource unavailable to its intended users, the attack is called:
A: tarvation attack
B: slow read attack
C: denial-of-service attack
D: spoofed attack

C: denial-of-service attack

How well did you know this?

Not at all

Perfectly

In operating system, each process has its own:
A: open files
B: address space and global variables
C: all of the mentioned
D: pending alarms, signals and signal handlers

C: all of the mentioned

How well did you know this?

Not at all

Perfectly

In UNIX, even an ’empty’ disk has a percentage of its space lost to:
A: stacks
B: programs
C: inodes
D: virtual memory

C: inodes

How well did you know this?

Not at all

Perfectly

Swap space exists in:
A: primary memory
B: secondary memory
C: cpu
D: none of the mentioned

B: secondary memory

How well did you know this?

Not at all

Perfectly

_____ is the concept in which a process is copied into main memory from the secondary memory according to the requirement.
A: Swapping
B: Paging
C: Segmentation
D: Demand paging

D: Demand paging

How well did you know this?

Not at all

Perfectly

The minimum number of frames to be allocated to a process is decided by the:
A: the amount of available physical memory
B: none of the mentioned
C: operating System
D: instruction set architecture

D: instruction set architecture

How well did you know this?

Not at all

Perfectly

What is all-or-nothing situation for sharing in memory?
A: Program makes all its data available to be accessed
B: It prohibits access to some
C: It separates program memory and data memory
D: It creates rules who can access program memory

A: Program makes all its data available to be accessed

How well did you know this?

Not at all

Perfectly

Those processes should be aborted on occurrence of a deadlock, the termination of which: A: safety is not hampered B: all of the mentioned C: is more time consuming D: incurs minimum cost

D: incurs minimum cost

Which two rights allow a process to change the entries in a column? A: owner and transfer B: deny and copy C: copy and transfer D: copy and owner

C: copy and transfer

RPC provides a(an) --?-- on the client side, a separate one for each remote procedure. A: identifier B: name C: process identifier D: stub

D: stub

If the swap space is simply a large file, within the file system, --?-- used to create it, name it and allocate its space. A: swap space storage manager is B: normal file system routines cannot be C: special routines must be D: normal file system routines can be

D: normal file system routines can be

When the valid – invalid bit is set to valid, it means that the associated page: A: is the system’s physical address space B: is in the process’s logical address space C: is in the TLB D: has data in it

B: is in the process’s logical address space

Multipartite viruses attack on: A: files B: memory C: all of the mentioned D: boot sector

C: all of the mentioned

Cancellation point is the point where: A: the thread can be cancelled – safely or otherwise doesn’t matter B: the thread can be cancelled safely C: the whole process can be cancelled safely D: none of the mentioned

B: the thread can be cancelled safely

In paging the user provides only --?-- which is partitioned by the hardware into --?-- and --?-- A: one offset, page number, address B: page number, offset, address C: none of the mentioned D: one address, page number, offset

D: one address, page number, offset

The priority of a real time task: A: none of the mentioned B: must degrade over time C: must not degrade over time D: may degrade over time

C: must not degrade over time

What are various roles of protection? A: It is used to optimize system downtime B: It is used to detect errors which can prevent contamination of system C: None of the mentioned D: It is used used to accelerate a process

B: It is used to detect errors which can prevent contamination of system

A set of processes is deadlock if: A: all processes are trying to kill each other B: each process is blocked and will remain so forever C: none of the mentioned D: each process is terminated

B: each process is blocked and will remain so forever

In the Many to One model, if a thread makes a blocking system call: A: none of the mentioned B: the entire process will run C: a part of the process will stay blocked, with the rest running D: the entire process will be blocked

D: the entire process will be blocked

The two methods how LRU page replacement policy can be implemented in hardware are: A: RAM & Registers B: Stack & Counters C: Registers & RAM D: Counters & Registers

B: Stack & Counters

When is the Many to One model at an advantage? A: When there is a single processor B: None of the mentioned C: When the program has to be multi-threaded D: When the program does not need multithreading

D: When the program does not need multithreading

A process can be: A: single threaded B: both single threaded and multithreaded C: none of the mentioned D: multithreaded

B: both single threaded and multithreaded

An I/O bound program will typically have: A: many very short I/O bursts B: many very short CPU bursts C: a few very short CPU bursts D: a few very short I/O bursts

B: many very short CPU bursts

An absolute path name begins at the: A: stem B: root C: current directory D: leaf

B: root

On most computer systems, the internal components are designed around a common: A: word size B: byte size C: protocol D: interface

A: word size

Real time systems must have: A: non preemptive kernels B: neither preemptive nor non preemptive kernels C: preemptive kernels or non preemptive kernels D: preemptive kernels

D: preemptive kernels

A program is generally composed of several different localities, which --?-- overlap. A: do not B: must C: must not D: may

D: may

A page fault occurs when: A: a page is invisible B: a page cannot be accessed due to its absence from memory C: a page gives inconsistent data D: all of the mentioned

B: a page cannot be accessed due to its absence from memory

A multilevel page table is preferred in comparison to a single level page table for translating virtual address to physical address because: A: it helps to reduce the size of page table needed to implement the virtual address space of a process B: it reduces the memory access time to read or write a memory location C: it is required by the translation lookaside buffer D: it helps to reduce the number of page faults in page replacement algorithms

A: it helps to reduce the size of page table needed to implement the virtual address space of a process

A thread is also called: A: Heavy Weight Process(HWP) B: Process C: None of the mentioned D: Light Weight Process(LWP)

D: Light Weight Process(LWP)

With relocation and limit registers, each logical address must be --?-- the limit register. A: greater than B: less than C: equal to D: none of the mentioned

B: less than

The interrupt vector contains: A: the interrupts B: the identifiers of interrupts C: the memory addresses of specialized interrupt handlers D: the device addresses

C: the memory addresses of specialized interrupt handlers

Consider a machine in which all memory reference instructions have only one memory address, for them we need at least --?-- frame(s). A: one B: none of the mentioned C: two D: three

C: two

The way/s in which a process responds to a signal are: A: performing some default action B: handling the signal C: ignoring the signal D: all of the mentioned

D: all of the mentioned

The growing phase is a phase in which: A: A transaction may release locks, and does obtain new locks B: A transaction may obtain locks, and releases a few or all of them C: A transaction may release locks, but does not obtain any new locks D: A transaction may obtain locks, but does not release any

D: A transaction may obtain locks, but does not release any

For a domain _______ is a list of objects together with the operation allowed on these objects. A: access list B: both capability and access list C: none of the mentioned D: capability list

D: capability list

A non blocking system call: A: halts the execution of the application for an extended time B: none of the mentioned C: does not block the interrupts D: does not halt the execution of the application

D: does not halt the execution of the application

Scheduling is done so as to:

Increase Throughput

What is best solution to have effect of unbounded number if base/bound registers? A: Tagged architecture B: Segmentation C: Fence method D: None of the mentioned

B: Segmentation

The file name is generally split into two parts: A: extension & name B: name & identifier C: type & extension D: identifier & type

A: extension & name

If multiple threads are concurrently searching through a database and one thread returns the result then the remaining threads must be: A: protected B: cancelled C: continued D: none of the mentioned

B: cancelled

The page table registers should be built with: A: very low speed logic B: none of the mentioned C: very high speed logic D: a large memory space

C: very high speed logic

An interrupt vector: A: is a unique identity given to an interrupt B: none of the mentioned C: is a unique device number that is indexed by an address D: is an address that is indexed to an interrupt handler

D: is an address that is indexed to an interrupt handler

The FAT is used much as a: A: stack B: linked list C: data D: pointer

B: linked list

Event latency is: A: the amount of time from event occurrence till the event crashes B: the amount of time an event takes to occur from when the system started C: the amount of time from the event occurrence till the system stops D: the amount of time that elapses from when an event occurs to when it is serviced.

D: the amount of time that elapses from when an event occurs to when it is serviced.

Messages sent by a process: A: have to be a variable size B: None of the mentioned C: can be fixed or variable sized D: have to be of a fixed size

C: can be fixed or variable sized

If a process is executing in its critical section, then no other processes can be executing in their critical section. This condition is called: A: critical exclusion B: mutual exclusion C: asynchronous exclusion D: synchronous exclusion

B: mutual exclusion

With a shared file: A: the changes made by one person are not reflected to the other B: there are two copies of the file C: actual file exists D: the changes made by one person are reflected to the other

D: the changes made by one person are reflected to the other

If a thread invokes the exec system call: A: none of the mentioned B: the exec is ignored as it is invoked by a thread. C: only the exec executes as a separate process. D: the program specified in the parameter to exec will replace the entire process

D: the program specified in the parameter to exec will replace the entire process

Every time a request for allocation cannot be granted immediately, the detection algorithm is invoked. This will help identify: A: the set of processes in the deadlock queue B: the set of processes that have been deadlocked C: the specific process that caused the deadlock D: all of the mentioned

B: the set of processes that have been deadlocked

Which of the following does not interrupt a running process? A: Scheduler process B: A device C: Timer D: Power failure

A: Scheduler process

The header and trailer of a sector contain information used by the disk controller such as --?-- and --?-- A: main section & disk identifier B: sector number & main section C: error correcting codes (ECC) & sector number D: disk identifier & sector number

C: error correcting codes (ECC) & sector number

Once the changes are written to the log, they are considered to be: A: completed B: committed C: none of the mentioned D: aborted

B: committed

The idea behind thread pools is: A: none of the mentioned B: all threads in a pool distribute the task equally among themselves C: a number of threads are created at process startup and placed in a pool where they sit and wait for work D: when a process begins, a pool of threads is chosen from the many existing and each thread is allotted equal amount of work

C: a number of threads are created at process startup and placed in a pool where they sit and wait for work

A process is thrashing if: A: it spends a lot of time executing, rather than paging B: it has no memory allocated to it C: none of the mentioned D: it spends a lot of time paging, than executing

D: it spends a lot of time paging, than executing

A floppy disk is designed to rotate --?-- as compared to a hard disk drive. A: none of the mentioned B: faster C: at the same speed D: slower

D: slower

Bounded capacity and Unbounded capacity queues are referred to as: A: User defined buffering B: Programmed buffering C: No buffering D: Automatic buffering

D: Automatic buffering

An IPC facility provides at least two operations: A: delete & receive message B: receive & send message C: write & delete message D: send & delete message

B: receive & send message

A semaphore is a shared integer variable: A: that can not be more than one B: that can not drop below zero C: that can not be more than zero D: that can not drop below one

B: that can not drop below zero

When a process closes the file: A: none of the mentioned B: all of the mentioned C: per-process table entry is not removed D: system wide entry’s open count is decremented

D: system wide entry’s open count is decremented

The --?-- program initializes all aspects of the system, from CPU registers to device controllers and the contents of main memory, and then starts the operating system. A: rom B: main C: bootstrap D: bootloader

C: bootstrap

How is disadvantage of all-or-nothing approach overcome? A: Fence method B: Tagged architecture C: Base/Bound D: Relocation technique

B: Tagged architecture

When a process blocks the receipt of certain signals: A: The signals are received until they are unblocked B: The signals are delivered C: The signals are received by the process once they are delivered D: The signals are not delivered

B: The signals are delivered

Segment replacement algorithms are more complex than page replacement algorithms because: A: Pages are better than segments B: Segments have fixed sizes C: Segments are better than pages D: Segments have variable sizes

D: Segments have variable sizes

--?-- replacement generally results in greater system throughput. A: Universal B: Public C: Local D: Global

D: Global

The --?-- maintains pending and blocked bit vectors in context of each process. A: CPU B: Memory C: Process D: Kernel

D: Kernel

--?-- controller sends the command placed into it, via messages to the --?-- controller. A: host, host B: disk, disk C: host, disk D: disk, host

C: host, disk

If too little space is allocated to a file: A: the file cannot be extended B: the file cannot be opened C: there will not be any space for the data, as the FCB takes it all D: the file will not work

A: the file cannot be extended

When a client has a cascading mount, --?-- server(s) is/are involved in a path name traversal. A: more than two B: at least one C: more than three D: more than one

D: more than one

A thread shares its resources(like data section, code section, open files, signals) with: A: other threads that belong to the same process B: other threads that belong to similar processes C: all of the mentioned D: other process similar to the one that the thread belongs to

A: other threads that belong to the same process

If the offset is legal: A: it is added to the segment base to produce the physical memory address B: it is used as a physical memory address itself C: it is subtracted from the segment base to produce the physical memory address D: none of the mentioned

B: it is used as a physical memory address itself

Thread cancellation is: A: the task of terminating a thread before it has completed B: none of the mentioned C: the task of removing a thread once its work is done D: the task of destroying the thread once its work is done

A: the task of terminating a thread before it has completed

The protection domain of a process contains: A: object name B: rights-set C: both object name and rights-set D: none of the mentioned

C: both object name and rights-set

Virtual memory allows: A: a program to be larger than the secondary storage B: execution of a process without being in physical memory C: execution of a process that may not be completely in memory D: a program to be smaller than the physical memory

C: execution of a process that may not be completely in memory

Cost factors of process termination include: A: All of the mentioned B: Number of resources the deadlock process is not holding C: CPU utilization at the time of deadlock D: Amount of time a deadlocked process has thus far consumed during its execution

D: Amount of time a deadlocked process has thus far consumed during its execution

In fixed size partition, the degree of multiprogramming is bounded by: A: the number of partitions B: all of the mentioned C: the CPU utilization D: the memory size

A: the number of partitions

In which type of allocation method each file occupy a set of contiguous block on the disk? A: dynamic-storage allocation B: linked allocation C: indexed allocation D: contiguous allocation

D: contiguous allocation

In a safety critical system, incorrect operation: A: does not affect much B: causes minor problems C: none of the mentioned D: causes major and serious problems

D: causes major and serious problems

The base register is also known as the: A: regular register B: relocation register C: basic register D: delocation register

B: relocation register

If the set of resources available to the process is fixed throughout the process’s lifetime then its domain is: A: dynamic B: neither static nor dynamic C: static D: none of the mentioned

C: static

In the Many to Many model when a thread performs a blocking system call: A: other threads are strictly prohibited from running B: other threads are allowed to run C: none of the mentioned D: other threads only from other processes are allowed to run

B: other threads are allowed to run

Which of the following algorithms tends to minimize the process flow time? A: First come First served B: Earliest Deadline First C: Shortest Job First D: Longest Job First

C: Shortest Job First

If working set window is too small: A: none of the mentioned B: it will not encompass entire locality C: it may overlap several localities D: it will cause memory problems

B: it will not encompass entire locality

If the extents are too large, then the problem that comes in is: A: internal fragmentation B: all of the mentioned C: external fragmentation D: starvation

A: internal fragmentation

Bounded waiting implies that there exists a bound on the number of times a process is allowed to enter its critical section: A: none of the mentioned B: before a process has made a request to enter its critical section C: when another process is in its critical section D: after a process has made a request to enter its critical section and before the request is granted

D: after a process has made a request to enter its critical section and before the request is granted

Concurrent access to shared data may result in: A: data inconsistency B: data consistency C: none of the mentioned D: data insecurity

A: data inconsistency

The wait operation of the semaphore basically works on the basic --?-- system call. A: wait() B: hold() C: block() D: stop()

C: block()

--?-- tend to represent a major bottleneck in system performance. A: Disks B: CPUs C: Programs D: I/O

A: Disks

When an entire committed transaction is completed: A: it is stored in the memory B: it is removed from the log file C: it is redone D: none of the mentioned

B: it is removed from the log file

Every address generated by the CPU is divided into two parts: A: frame offset & page offset B: frame bit & page number C: page offset & frame bit D: page number & page offset

D: page number & page offset

The percentage of times a page number is found in the TLB is known as: A: None of the mentioned B: miss percent C: miss ratio D: hit ratio

D: hit ratio

The time required to create a new thread in an existing process is: A: equal to the time required to create a new process B: greater than the time required to create a new process C: none of the mentioned D: less than the time required to create a new process

D: less than the time required to create a new process

In the single level directory: A: All files are contained in different directories all at the same level B: Depends on the operating system C: All files are contained in the same directory D: None of the mentioned

C: All files are contained in the same directory

DMA is used for: A: Utilizing CPU cycles B: Low speed devices C: All of the mentioned D: High speed devices(disks and communications network)

D: High speed devices(disks and communications network)

When device A has a cable that plugs into device B, and device B has a cable that plugs into device C and device C plugs into a port on the computer, this arrangement is called a _________ A: cable B: bus C: port D: daisy chain

D: daisy chain

An --?-- uniquely identifies processes and is used to provide address space protection for that process. A: address space identifier B: None of the mentioned C: address process identifier D: address space locator

A: address space identifier

When the entries in the segment tables of two different processes point to the same physical location: A: the segments are invalid B: all of the mentioned C: segments are shared D: the processes get blocked

C: segments are shared

From the following, which is not a common file permission? A: Read B: Stop C: Execute D: Write

B: Stop

--?-- writes occur in the order in which the disk subsystem receives them, and the writes are not buffered. A: Synchronous B: Regular C: Irregular D: Asynchronous

A: Synchronous

Most time-sharing systems rely on --?-- to manage memory space. A: interrupts B: roll-in/roll-out C: polling D: time-slicing

D: time-slicing

A --?-- is a collection of electronics that can operate a port, a bus, or a device. A: driver B: controller C: host D: bus

B: controller

Deadlock prevention is a set of methods: A: to ensure that at least one of the necessary conditions cannot hold B: to ensure that all of the necessary conditions do not hold C: to recover from a deadlock D: to decide if the requested resources for a process have to be given or not

A: to ensure that at least one of the necessary conditions cannot hold

Thread pools are useful when: A: when we need to limit the number of threads running in the application at the same time B: when we need to limit the number of threads running in the application as a whole C: none of the mentioned D: when we need to arrange the ordering of threads

A: when we need to limit the number of threads running in the application at the same time

The pattern that can be used to identify a virus is known as: A: multipartite B: armoured C: virus signature D: stealth

C: virus signature

Which of the following scheduling algorithms gives minimum average waiting time? A: SJF B: FCFS C: Priority D: Round – robin

A: SJF

Which of the following is TRUE? A: Overlays are used to increase the size of physical memory B: Overlays are used whenever the physical address space is smaller than the logical address space C: Overlays are used to increase the logical address space D: When overlays are used, the size of a process is not limited to the size of the physical memory

D: When overlays are used, the size of a process is not limited to the size of the physical memory

The interval from the time of submission of a process to the time of completion is termed as: A: response time B: turnaround time C: throughput D: waiting time

B: turnaround time

Under --?--, programs are divided into variable length pieces. A: dynamic memory management B: fixed partitions C: paging D: segmentation

D: segmentation

Mapping of file is managed by: A: page table B: file system C: file metadata D: virtual memory

C: file metadata

Interrupt latency refers to the period of time: A: from arrival of an interrupt to the start of the interrupt service routine B: none of the mentioned C: from the occurrence of an event to the arrival of an interrupt D: from the occurrence of an event to the servicing of an interrupt

A: from arrival of an interrupt to the start of the interrupt service routine

Scheduling is done so as to: A: keep the waiting time the same B: increase the waiting time C: decrease the waiting time D: none of the mentioned

C: decrease the waiting time

Each entry in a Translation lookaside buffer (TLB) consists of: A: key B: constant C: value D: bit value

A: key

The number of processes completed per unit time is known as: A: Output B: Capacity C: Throughput D: Efficiency

C: Throughput

The advantage of dynamic loading is that: A: A used routine is used multiple times B: CPU utilization increases C: An unused routine is never loaded D: All of the mentioned

C: An unused routine is never loaded

When a program tries to access a page that is mapped in address space but not loaded in physical memory, then: A: segmentation fault occurs B: no error occurs C: fatal error occurs D: page fault occurs

D: page fault occurs

What is the drawback of banker’s algorithm? A: in advance processes rarely know that how much resource they will need B: all of the mentioned C: the number of processes changes as time progresses D: resource once available can disappear

B: all of the mentioned

A Process Control Block(PCB) does not contain which of the following: A: Bootstrap program B: Stack C: Data D: Code

A: Bootstrap program

Each --?-- has its own index block. A: file B: address C: partition D: all of the mentioned

A: file

Given a priori information about the --?-- number of resources of each type that maybe requested for each process, it is possible to construct an algorithm that ensures that the system will never enter a deadlock state. A: average B: approximate C: minimum D: maximum

D: maximum

Physical memory is broken into fixed-sized blocks called: A: backing store B: pages C: none of the mentioned D: frames

D: frames

The resource allocation graph is not applicable to a resource allocation system: A: none of the mentioned B: with a single instance of each resource type C: with multiple instances of each resource type D: single & multiple instance of each resource type

C: with multiple instances of each resource type

The --?-- time in a swap out of a running process and swap in of a new process into the memory is very high. A: execution B: waiting C: all of the mentioned D: context – switch

D: context – switch

How does the Hardware trigger an interrupt? A: Executing a special program called interrupt program B: Sending signals to CPU through system bus C: Executing a special program called system program D: Executing a special operation called system call

B: Sending signals to CPU through system bus

To access the services of operating system, the interface is provided by the: A: System calls B: Library C: API D: Assembly instructions

A: System calls

Which of the following is FALSE? A: Blocking one kernel level thread blocks all other related threads B: Related kernel level threads can be scheduled on different processors in a multiprocessor system C: Context switch time is longer for kernel level threads than for user level threads D: User level threads do not need any hardware support

A: Blocking one kernel level thread blocks all other related threads

Operating System maintains the page table for: A: each thread B: each process C: each address D: each instruction

B: each process

The disadvantage of invoking the detection algorithm for every request is: A: all of the mentioned B: overhead of the detection algorithm due to consumption of memory C: excessive time consumed in the request to be allocated memory D: considerable overhead in computation time

D: considerable overhead in computation time

Caching is --?-- spooling. A: all of the mentioned B: same as C: not the same as D: none of the mentioned

C: not the same as

Effective access time is directly proportional to: A: memory access time B: page-fault rate C: none of the mentioned D: hit ratio

B: page-fault rate

Defective sectors on disks are often known as: A: none of the mentioned B: bad blocks C: good blocks D: destroyed blocks

B: bad blocks

What is interprocess communication? A: communication within the process B: none of the mentioned C: communication between two process D: communication between two threads of same process

C: communication between two process

For real time operating systems, interrupt latency should be: A: maximum B: zero C: minimal D: dependent on the scheduling

C: minimal

External fragmentation will not occur when: A: first fit is used B: best fit is used C: worst fit is used D: no matter which algorithm is used, it will always occur

D: no matter which algorithm is used, it will always occur

In the --?-- algorithm, the disk arm goes as far as the final request in each direction, then reverses direction immediately without going to the end of the disk. A: C-LOOK B: C-SCAN C: SCAN D: LOOK

D: LOOK

The operations that can be invoked on a condition variable are: A: signal & hold B: hold & wait C: continue & signal D: wait & signal

D: wait & signal

The real difficulty with SJF in short term scheduling is: A: it is too complex to understand B: it is too good an algorithm C: knowing the length of the next CPU request D: none of the mentioned

C: knowing the length of the next CPU request

A synchronious event that is generated when the processor detects a predefined condition is called a(n): A: exception B: page fault C: interrupt D: the IDT

A: exception

The operating system's routines perform key support functions such as: A: accepting and carrying out user commands B: both C: communicating with peripheral devices

B: both

In the Many to Many model true concurrency cannot be gained because: A: none of the mentioned B: the kernel can schedule only one thread at a time C: there are too many threads to handle D: it is hard to map threads with each other

B: the kernel can schedule only one thread at a time

A monitor is a type of: A: high level synchronization construct B: none of the mentioned C: semaphore D: low level synchronization construct

A: high level synchronization construct

Write ahead logging is a way: A: to ensure atomicity B: all of the mentioned C: to keep data consistent D: that records data on stable storage

B: all of the mentioned

What is trap door? A: It is a Trojan horse B: It is a virus which traps and locks user terminal C: It is a hole in software left by designer D: It is trap door in WarGames

C: It is a hole in software left by designer

Multimedia systems require --?-- scheduling to ensure critical tasks will be serviced within timing deadlines. A: normal B: hard real time C: none of the mentioned D: soft real time

B: hard real time

In the tree structured directories: A: the tree has the leaf directory B: all of the mentioned C: the tree has the stem directory D: the tree has the root directory

D: the tree has the root directory

Under multiprogramming, turnaround time for short jobs is usually --?-- and that for long jobs is slightly --?-- A: Shortened; Lengthened B: Lengthened; Shortened C: Shortened; Shortened D: Shortened; Unchanged

A: Shortened; Lengthened

File virus attaches itself to the A: all of the mentioned B: source file C: executable file D: object file

C: executable file

When a web page is loading, and the user presses a button on the browser to stop loading the page: A: the thread loading the page continues with the loading B: the thread loading the page is paused C: the thread loading the page does not stop, but continues with another task D: the thread loading the page is cancelled

D: the thread loading the page is cancelled

The directory can be viewed as a --?-- that translates file names into their directory entries. A: swap space B: cache C: symbol table D: partition

C: symbol table

The time taken for the desired sector to rotate to the disk head is called: A: rotational latency B: random access time C: seek time D: positioning time

A: rotational latency

When in contiguous allocation the space cannot be extended easily: A: the file gets destroyed B: the contents of the file have to be copied to a new space, a larger hole C: the file will get formatted and lost all its data D: none of the mentioned

B: the contents of the file have to be copied to a new space, a larger hole

Users and application programmers communicate with hardware through: A: program instructions B: a channel C: the operating system D: all of the mentioned

C: the operating system

What is a long-term scheduler? A: None of the mentioned B: It selects which process has to be brought into the ready queue C: It selects which process to remove from memory by swapping D: It selects which process has to be executed next and allocates CPU

B: It selects which process has to be brought into the ready queue

Anonymous access allows a user to transfer files: A: only if he has an account on the remote system B: without having an account on the remote system C: none of the mentioned D: only if he accesses the system with a guest account

B: without having an account on the remote system

Signals that occur at the same time, are presented to the process: A: one at a time, in no particular order B: none of the mentioned C: all at a time D: one at a time, in a particular order

A: one at a time, in no particular order

With round robin scheduling algorithm in a time shared system: A: using very small time slices converts it into First come First served scheduling algorithm B: using extremely small time slices increases performance C: using very large time slices converts it into First come First served scheduling algorithm D: using very small time slices converts it into Shortest Job First algorithm

C: using very large time slices converts it into First come First served scheduling algorithm

Memory management units: A: increase the power consumption of the system B: increase the cost of the system C: increase the time required to complete an operation D: all of the mentioned

D: all of the mentioned

A circular buffer: A: all of the mentioned B: overwrites older values as it goes C: none of the mentioned D: writes to the end of its space and then continues at the beginning

D: writes to the end of its space and then continues at the beginning

______ is an approach to restricting system access to authorized users. A: Job-based access control B: Role-based access control C: None of the mentioned D: Process-based access control

B: Role-based access control

The technique of duplicating every disk is known as: A: shadowing B: redundancy C: mirroring D: all of the mentioned

C: mirroring

Path names can be of two types: A: absolute & relative B: relative & local C: global & relative D: local & global

A: absolute & relative

When two users keep a subdirectory in their own directories, the structure being referred to is: A: cyclic graph directory structure B: acyclic graph directory C: two level directory structure D: tree structure

B: acyclic graph directory

What is not a good practice for user administration? A: Isolating a system after a compromise B: Perform random auditing procedures C: Using telnet and FTP for remote access D: Granting privileges on a per host basis

C: Using telnet and FTP for remote access

The size of a process is limited to the size of: A: physical memory B: external storage C: secondary storage D: none of the mentioned

A: physical memory

The child process completes execution,but the parent keeps executing, then the child process is known as: A: Body B: Zombie C: Orphan D: Dead

B: Zombie

The --?-- table contains the base address of each page in physical memory. A: page B: frame C: memory D: process

A: page

For every process there is a: A: all of the mentioned B: page table C: copy of page table D: pointer to page table

B: page table

The segment base contains the: A: starting physical address of the segment in memory B: none of the mentioned C: segment length D: starting logical address of the process

A: starting physical address of the segment in memory

The host sets --?-- bit when a command is available for the controller to execute. A: status B: command-ready C: write D: control

B: command-ready

If the resources are always preempted from the same process, --?-- can occur. A: deadlock B: system crash C: aging D: starvation

D: starvation

In real time operating system: A: a task must be serviced by its deadline period B: process scheduling can be done only once C: all processes have the same priority D: kernel is not required

A: a task must be serviced by its deadline period

Which one of the following is the deadlock avoidance algorithm? A: banker’s algorithm B: round-robin algorithm C: karn’s algorithm D: elevator algorithm

A: banker’s algorithm

Data cannot be written to secondary storage unless written within a: A: text format B: swap space C: file D: directory

C: file

If one or more devices use a common set of wires to communicate with the computer system, the connection is called: A: Bus B: CPU C: Wirefull D: Monitor

A: Bus

Whenever a process needs I/O to or from a disk it issues a: A: system call to the CPU B: a special procedure C: all of the mentioned D: system call to the operating system

D: system call to the operating system

Virtual memory uses disk space as an extension of: A: secondary storage B: none of the mentioned C: main memory D: tertiary storage

C: main memory

A large number of disks in a system improves the rate at which data can be read or written: A: if the disks are operated in parallel B: if the disks are operated on sequentially C: all of the mentioned D: if the disks are operated on selectively

A: if the disks are operated in parallel

The signal operation of the semaphore basically works on the basic --?-- system call. A: getup() B: wakeup() C: continue() D: start()

B: wakeup()

In linked allocation: A: each file must occupy a set of contiguous blocks on the disk B: none of the mentioned C: all the pointers to scattered blocks are placed together in one location D: each file is a linked list of disk blocks

D: each file is a linked list of disk blocks

Disks are segmented into one or more partitions, each containing a file system or: A: made into backup space B: made into swap space C: left ‘raw’ D: left ‘ripe’

C: left ‘raw’

Using a pager: A: decreases the swap time & amount of physical memory needed B: increases the amount of physical memory needed C: increases the swap time D: decreases the swap time

A: decreases the swap time & amount of physical memory needed

The relocation register helps in: A: protecting the address spaces of processes B: none of the mentioned C: a different address space to processes D: providing more address space to processes

A: protecting the address spaces of processes

Which of the following do not belong to queues for processes? A: PCB queue B: Device Queue C: Ready Queue D: Job Queue

A: PCB queue

Windows NT uses a --?-- implementation for I/O A: message – passing B: secondary memory C: draft – passing D: cache

A: message – passing

The operating system and the other processes are protected from being modified by an already running process because: A: they have a protection algorithm B: they are in different logical addresses C: every address generated by the CPU is being checked against the relocation and limit registers D: they are in different memory spaces

C: every address generated by the CPU is being checked against the relocation and limit registers

Which of the following calls never returns an error? A: ioctl B: getpid C: fork D: open

B: getpid

In SCSI disks used in high end PCs, the controller maintains a list of --?-- on the disk. The disk is initialized during --?-- formatting which sets aside spare sectors not visible to the operating system. A: bad blocks, partitioning B: destroyed blocks, partitioning C: destroyed blocks, high level formatting D: bad blocks, low level formatting

D: bad blocks, low level formatting

If a process needs I/O to or from a disk, and if the drive or controller is busy then: A: the request will be placed in the queue of pending requests for that drive B: the request will not be processed and will be ignored completely C: none of the mentioned D: the request will be not be placed

A: the request will be placed in the queue of pending requests for that drive

In addition to providing a user interface, the operating system: A: manages system resources B: complicates programming

A: manages system resources

Illegal addresses are trapped using the --?-- bit. A: error B: protection C: valid – invalid D: access

C: valid – invalid

Working set model for page replacement is based on the assumption of: A: locality B: random access C: modularity D: globalization

A: locality

For Mutual exclusion to prevail in the system: A: the processor must be a uniprocessor rather than a multiprocessor B: at least one resource must be held in a non sharable mode C: all of the mentioned D: there must be at least one resource in a sharable mode

B: at least one resource must be held in a non sharable mode

A monitor is characterized by: A: all of the mentioned B: a set of programmer defined operators C: an identifier D: the number of variables in it

B: a set of programmer defined operators

Pages are swapped into and out from the real memory: A: page pool B: V-R area C: partitions D: paging device

A: page pool

In the non blocking send: A: the sending process keeps sending until it receives a message B: the sending process sends the message and resumes operation C: none of the mentioned D: the sending process keeps sending until the message is received

B: the sending process sends the message and resumes operation

CPU scheduling is the basis of: A: larger memory sized systems B: multiprocessor systems C: none of the mentioned D: multiprogramming operating systems

D: multiprogramming operating systems

If one thread opens a file with read privileges then: A: any other thread can not read from that file B: all of the mentioned C: other threads in the same process can also read from that file D: other threads in the another process can also read from that file

C: other threads in the same process can also read from that file

If the number of cycles spent busy – waiting is not excessive, then: A: none of the mentioned B: both programmed and interrupt driven I/O are equally efficient C: interrupt driven I/O is more efficient than programmed I/O D: programmed I/O is more efficient than interrupt driven I/O

D: programmed I/O is more efficient than interrupt driven I/O

Which one of the following is a process that uses the spawn mechanism to revage the system performance? A: threat B: worm C: virus D: trojan

B: worm

Time required to synchronous switch from the context of one thread to the context of another thread is called: A: jitter B: threads fly-back time C: context switch time D: none of the mentioned

C: context switch time

Which one of the following is a visual ( mathematical ) way to determine the deadlock occurrence? A: inversion graph B: starvation graph C: none of the mentioned D: resource allocation graph

D: resource allocation graph

For larger page tables, they are kept in main memory and a --?-- points to the page table. A: page table base pointer B: page table base register C: page table base D: page table register pointer

B: page table base register

Why is it difficult to revoke capabilities? A: They are distributed throughout the system B: They are not defined precicely C: None of the mentioned D: They are too many

A: They are distributed throughout the system

A write of a block has to access: A: a parity block B: parity disk C: all of the mentioned D: the disk on which the block is stored

C: all of the mentioned

A deadlock can be broken by: A: none of the mentioned B: abort all the process in the system C: preempt all resources from all processes D: abort one or more processes to break the circular wait

D: abort one or more processes to break the circular wait

The open file table has a/an --?-- associated with each file. A: file content B: file permission C: close count D: open count

D: open count

Process synchronization can be done on: A: none of the mentioned B: both hardware and software level C: software level D: hardware level

B: both hardware and software level

What is true about Indirection to revoke capability? A: This system was adopted in MULTICS system B: Capabilities point indirectly to the objects C: Each capability will not have a unique entry in global D: Table entries cannot be reused for other capabilities

B: Capabilities point indirectly to the objects

Optimal page – replacement algorithm is difficult to implement, because: A: it requires a lot of information B: it is extremely expensive C: it is too complex D: it requires future knowledge of the reference string

D: it requires future knowledge of the reference string

If the sum of the working – set sizes increases, exceeding the total number of available frames: A: the operating system selects a process to suspend B: then the process crashes C: the system crashes D: the memory overflows

A: the operating system selects a process to suspend

Suppose that a process is in “Blocked” state waiting for some I/O service. When the service is completed, it goes to the: A: Suspended state B: Ready state C: Terminated state D: Running state

B: Ready state

Some directory information is kept in main memory or cache to: A: speed up access B: increase free space in secondary storage C: fill up the cache

A: speed up access

A better way of contiguous allocation to extend the file size is: A: adding an extent (another chunk of contiguous space) B: adding an index table to the first contiguous block C: none of the mentioned D: adding pointers into the first contiguous block

A: adding an extent (another chunk of contiguous space)

Which one of the following explains the sequential file access method? A: read bytes one at a time, in order B: read/write sequentially by record C: read/write randomly by record D: random access according to the given byte number

A: read bytes one at a time, in order

For swap space created in a separate disk partition where no file system or directory structure is placed, --?-- used to allocate and deallocate the blocks. A: normal file system routines can be B: swap space storage manager is C: special routines must be D: normal file system routines cannot be

B: swap space storage manager is

A semaphore: A: can be accessed from multiple processes B: is a binary mutex C: must be accessed from only one process D: none of the mentioned

A: can be accessed from multiple processes

Thread pools help in: A: servicing a single request using multiple threads from the pool B: none of the mentioned C: faster servicing of requests with an existing thread rather than waiting to create a new thread D: servicing multiple requests using one thread

C: faster servicing of requests with an existing thread rather than waiting to create a new thread

What are the different ways to intrude? A: Buffer overflows B: All of the mentioned C: Unexpected combinations and unhandled input D: Race conditions

B: All of the mentioned

In the following cases non – preemptive scheduling occurs: A: When a process switches from the running state to the ready state B: When a process switches from the waiting state to the ready state C: All of the mentioned D: When a process goes from the running state to the waiting state

D: When a process goes from the running state to the waiting state

The problem of priority inversion can be solved by: A: none of the mentioned B: priority inversion protocol C: both priority inheritance and inversion protocol D: priority inheritance protocol

D: priority inheritance protocol

Memory protection in a paged environment is accomplished by: A: restricted access rights to users B: protection bit with each page C: restriction on page visibility D: protection algorithm with each page

B: protection bit with each page

Which one of the following is not true? A: kernel is the program that constitutes the central core of the operating system B: kernel remains in the memory during the entire computer session C: kernel is the first part of operating system to load into memory during booting D: kernel is made of various modules which can not be loaded in running operating system

D: kernel is made of various modules which can not be loaded in running operating system

--?-- is generally faster than --?-- and --?-- A: best fit, first fit, worst fit B: none of the mentioned C: worst fit, best fit, first fit D: first fit, best fit, worst fit

D: first fit, best fit, worst fit

What is main objective of protection? A: Ensure that each object is accessed correctly and only by allowed processes B: Objects have different priority and thus different levels of protection C: None of the mentioned D: Ensure all objects are protected individually

A: Ensure that each object is accessed correctly and only by allowed processes

In general the two interrupt request lines are: A: blocked & non maskable interrupts B: none of the mentioned C: maskable & non maskable interrupts D: maskable & blocked interrupts

C: maskable & non maskable interrupts

On media that use constant linear velocity (CLV), the --?-- is uniform. A: density of bits per sector B: the density of bits per track C: none of the mentioned D: density of bits on the disk

B: the density of bits per track

Another solution to the problem of external fragmentation problem is to: A: permit smaller processes to be allocated memory at last B: all of the mentioned C: permit larger processes to be allocated memory at last D: permit the logical address space of a process to be noncontiguous

D: permit the logical address space of a process to be noncontiguous

When a page fault occurs, the state of the interrupted process is: A: saved B: none of the mentioned C: disrupted D: invalid

A: saved

What does access matrix represent? A: Rows-Domains, Columns-Objects B: Rows-Objects, Columns-Domains C: Rows-Domains, Columns-Access list D: Rows-Access List, Columns-Domains

A: Rows-Domains, Columns-Objects

When one thread immediately terminates the target thread, it is called: A: Systematic cancellation B: Sudden Termination C: Deferred cancellation D: Asynchronous cancellation

D: Asynchronous cancellation

Which of the following system calls does not return control to the calling point, on termination? A: ioctl B: longjmp C: exec D: fork

C: exec

Paging increases the --?-- time. A: waiting B: all of the mentioned C: execution D: context – switch

D: context – switch

For most computers, the bootstrap is stored in: A: RAM B: ROM C: Tertiary storage D: Cache

B: ROM

A fork system call will fail if: A: all of the mentioned B: the limit on the minimum number of processes that can be under execution by a single user would be executed C: the previously executed statement is also a fork call D: the limit on the maximum number of processes in the system would be executed

D: the limit on the maximum number of processes in the system would be executed