Category: Operating System Objective Questions

JUnit Problems on “File System Interface Directory Structure”.

1. An absolute path name begins at the _____________
a) leaf
b) stem
c) current directory
d) root

Answer: d

2. A relative path name begins at the _____________
a) leaf
b) stem
c) current directory
d) root

Answer: c

3. In a tree structure, when deleting a directory that is not empty?
a) The contents of the directory are safe
b) The contents of the directory are also deleted
c) contents of the directory are not deleted
d) none of the mentioned

Answer: b

4. When two users keep a subdirectory in their own directories, the structure being referred to is _____________
a) tree structure
b) cyclic graph directory structure
c) two level directory structure
d) acyclic graph directory

Answer: d

5. A tree structure ______ the sharing of files and directories.
a) allows
b) may restrict
c) restricts
d) none of the mentioned

Answer: c
Clarification: None.

6. With a shared file _____________
a) actual file exists
b) there are two copies of the file
c) the changes made by one person are not reflected to the other
d) the changes made by one person are reflected to the other

Answer: d
Clarification: None.

7. In UNIX, what is a link?
a) a directory entry
b) a pointer to another file or subdirectory
c) implemented as an absolute or relative path name
d) all of the mentioned

Answer: d
Clarification: None.

8. The operating system _______ the links when traversing directory trees, to preserve the acyclic structure of the system.
a) considers
b) ignores
c) deletes
d) none of the mentioned

Answer: b
Clarification: None.

9. The deletion of a link ________ the original file.
a) deletes
b) affects
c) does not affect
d) none of the mentioned

Answer: c
Clarification: None.

10. When keeping a list of all the links/references to a file, and the list is empty, implies that _____________
a) the file has no copies
b) the file is deleted
c) the file is hidden
d) none of the mentioned

Answer: b
Clarification: None.

11. When a cycle exists, the reference count maybe non zero, even when it is no longer possible to refer to a directory or file, due to _______
a) the possibility of one hidden reference
b) the possibility of two hidden references
c) the possibility of self referencing
d) none of the mentioned

Answer: c

Advanced Operating System Questions and Answers on “RAID Structure”.

1. A large number of disks in a system improves the rate at which data can be read or written if ____________
a) the disks are operated on sequentially
b) the disks are operated on selectively
c) the disks are operated in parallel
d) all of the mentioned

Answer: c
Clarification: None.

2. RAID stands for ____________
a) Redundant Allocation of Inexpensive Disks
b) Redundant Array of Important Disks
c) Redundant Allocation of Independent Disks
d) Redundant Array of Independent Disks

Answer: d
Clarification: None.

3. If the mean time to failure of a single disk is 100,000 hours, then the mean time to failure of some disk in an array of 100 disks will be ____________
a) 100 hours
b) 10 days
c) 10 hours
d) 1000 hours

Answer: d
Clarification: None.

4. The solution to the problem of reliability is the introduction of __________
a) aging
b) scheduling
c) redundancy
d) disks

Answer: c
Clarification: None.

5. The technique of duplicating every disk is known as ____________
a) mirroring
b) shadowing
c) redundancy
d) all of the mentioned

Answer: a
Clarification: None.

6. The mean time to failure of a mirrored disk depends on ____________
I) the mean time to failure of individual disks
II) the mean time to repair
a) Only I
b) Only II
c) Both I and II
d) Neither I nor II

Answer: c
Clarification: None.

7. RAID level ________ refers to disk arrays with striping at the level of blocks, but without any redundancy.
a) 0
b) 1
c) 2
d) 3

Answer: a
Clarification: None.

8. RAID level _______ refers to disk mirroring.
a) 0
b) 1
c) 2
d) 3

Answer: b
Clarification: None.

9. RAID level ______ is also known as bit interleaved parity organisation.
a) 0
b) 1
c) 2
d) 3

Answer: d
Clarification: None.

10. A single parity bit can be used for ____________
a) detection
b) multiple error corrections
c) few error corrections
d) all of the mentioned

Answer: a
Clarification: None.

11. RAID level ______ is also known as memory style error correcting code(ECC) organization.
a) 1
b) 2
c) 3
d) 4

Answer: b
Clarification: None.

12. RAID level 3 does not have _________ as in RAID level 1.
a) efficiency
b) enough storage space for data
c) storage overhead
d) time consumption overhead

Answer: c
Clarification: There is one mirror disk for every disk in level 1.

Operating System Multiple Choice Questions on “Process Structures”.

1. The initial program that is run when the computer is powered up is called __________
a) boot program
b) bootloader
c) initializer
d) bootstrap program

Answer: d
Clarification: None.

2. How does the software trigger an interrupt?
a) Sending signals to CPU through bus
b) Executing a special operation called system call
c) Executing a special program called system program
d) Executing a special program called interrupt trigger program

Answer: b
Clarification: None.

3. What is a trap/exception?
a) hardware generated interrupt caused by an error
b) software generated interrupt caused by an error
c) user generated interrupt caused by an error
d) none of the mentioned

Answer: b
Clarification: None.

4. What is an ISR?
a) Information Service Request
b) Interrupt Service Request
c) Interrupt Service Routine
d) Information Service Routine

Answer: c
Clarification: None.

5. What is an interrupt vector?
a) It is an address that is indexed to an interrupt handler
b) It is a unique device number that is indexed by an address
c) It is a unique identity given to an interrupt
d) None of the mentioned

Answer: a
Clarification: None.

6. DMA is used for __________
a) High speed devices(disks and communications network)
b) Low speed devices
c) Utilizing CPU cycles
d) All of the mentioned

Answer: a
Clarification: None.

7. In a memory mapped input/output __________
a) the CPU uses polling to watch the control bit constantly, looping to see if a device is ready
b) the CPU writes one data byte to the data register and sets a bit in control register to show that a byte is available
c) the CPU receives an interrupt when the device is ready for the next byte
d) the CPU runs a user written code and does accordingly

Answer: b
Clarification: None.

8. In a programmed input/output(PIO) __________
a) the CPU uses polling to watch the control bit constantly, looping to see if a device is ready
b) the CPU writes one data byte to the data register and sets a bit in control register to show that a byte is available
c) the CPU receives an interrupt when the device is ready for the next byte
d) the CPU runs a user written code and does accordingly

Answer: a
Clarification: None.

9. In an interrupt driven input/output __________
a) the CPU uses polling to watch the control bit constantly, looping to see if a device is ready
b) the CPU writes one data byte to the data register and sets a bit in control register to show that a byte is available
c) the CPU receives an interrupt when the device is ready for the next byte
d) the CPU runs a user written code and does accordingly

Answer: c
Clarification: None.

10. In the layered approach of Operating Systems __________
a) Bottom Layer(0) is the User interface
b) Highest Layer(N) is the User interface
c) Bottom Layer(N) is the hardware
d) Highest Layer(N) is the hardware

Answer: b
Clarification: None.

11. How does the Hardware trigger an interrupt?
a) Sending signals to CPU through a system bus
b) Executing a special program called interrupt program
c) Executing a special program called system program
d) Executing a special operation called system call

Answer: a
Clarification: None.

12. Which operation is performed by an interrupt handler?
a) Saving the current state of the system
b) Loading the interrupt handling code and executing it
c) Once done handling, bringing back the system to the original state it was before the interrupt occurred
d) All of the mentioned

Answer: d

Operating System Multiple Choice Questions on “Swapping Processes”.

1. What is Address Binding?
a) going to an address in memory
b) locating an address with the help of another address
c) binding two addresses together to form a new address in a different memory space
d) a mapping from one address space to another

Answer: d
Clarification: None.

2. Binding of instructions and data to memory addresses can be done at ____________
a) Compile time
b) Load time
c) Execution time
d) All of the mentioned

Answer: d
Clarification: None.

3. If the process can be moved during its execution from one memory segment to another, then binding must be ____________
a) delayed until run time
b) preponed to compile time
c) preponed to load time
d) none of the mentioned

Answer: a
Clarification: None.

4. What is Dynamic loading?
a) loading multiple routines dynamically
b) loading a routine only when it is called
c) loading multiple routines randomly
d) none of the mentioned

Answer: b
Clarification: None.

5. What is the advantage of dynamic loading?
a) A used routine is used multiple times
b) An unused routine is never loaded
c) CPU utilization increases
d) All of the mentioned

Answer: b
Clarification: None.

6. The idea of overlays is to ____________
a) data that are needed at any given time
b) enable a process to be larger than the amount of memory allocated to it
c) keep in memory only those instructions
d) all of the mentioned

Answer: d
Clarification: None.

7. The ___________ must design and program the overlay structure.
a) programmer
b) system architect
c) system designer
d) none of the mentioned

Answer: a
Clarification: None.

8. The ___________ swaps processes in and out of the memory.
a) Memory manager
b) CPU
c) CPU manager
d) User

Answer: a
Clarification: None.

9. If a higher priority process arrives and wants service, the memory manager can swap out the lower priority process to execute the higher priority process. When the higher priority process finishes, the lower priority process is swapped back in and continues execution. This variant of swapping is sometimes called?
a) priority swapping
b) pull out, push in
c) roll out, roll in
d) none of the mentioned

Answer: c
Clarification: None.

10. If binding is done at assembly or load time, then the process _____ be moved to different locations after being swapped out and in again.
a) can
b) must
c) can never
d) may

Answer: c
Clarification: None.

11. In a system that does not support swapping ____________
a) the compiler normally binds symbolic addresses (variables) to relocatable addresses
b) the compiler normally binds symbolic addresses to physical addresses
c) the loader binds relocatable addresses to physical addresses
d) binding of symbolic addresses to physical addresses normally takes place during execution

Answer: a
Clarification: None.

12. Which of the following is TRUE?
a) Overlays are used to increase the size of physical memory
b) Overlays are used to increase the logical address space
c) When overlays are used, the size of a process is not limited to the size of the physical memory
d) Overlays are used whenever the physical address space is smaller than the logical address space

Answer: c

Operating System Multiple Choice Questions on “Multimedia Systems”.

1. What is multimedia file?
a) is same as any other regular file
b) must be accessed at specific rate
c) stored on remote server can not be delivered to its client
d) none of the mentioned

Answer: b
Clarification: None.

2. In which type of streaming multimedia file is delivered to the client, but not shared?
a) real-time streaming
b) progressive download
c) compression
d) none of the mentioned

Answer: a
Clarification: None.

3. Which one of the following is the characteristic of a multimedia system?
a) high storage
b) high data rates
c) both high storage and high data rates
d) none of the mentioned

Answer: c
Clarification: None.

4. The delay that occur during the playback of a stream is called ___________
a) stream delay
b) playback delay
c) jitter
d) event delay

Answer: c
Clarification: None.

5. Which algorithm can be optimized to meet the timing deadlines and rate requirements of continuous media?
a) Earliest-Deadline-First scheduling
b) SCAN-EDF scheduling
c) Both Earliest-Deadline-First scheduling & SCAN-EDF scheduling
d) None of the mentioned

Answer: c
Clarification: None.

6. Real time streaming protocol is used ___________
a) to control streaming media servers
b) for establishing and controlling media sessions between endpoints
c) to provide real time control of playback of media files from the server
d) all of the mentioned

Answer: d
Clarification: None.

7. In teardown state of real time streaming protocol is ___________
a) the server resources for client
b) server delivers the stream to client
c) server suspends delivery of stream
d) server breaks down the connection

Answer: d
Clarification: None.

8. CineBlitz multimedia server supports ___________
a) real time clients
b) non-real time clients
c) both real time & non-real time clients
d) none of the mentioned

Answer: c
Clarification: None.

9. Multimedia system require hard real time scheduling ___________
a) to ensure critical tasks will be serviced within timing deadlines
b) to deliver the media file to the client
c) to minimize the delay
d) for security

Answer: a
Clarification: None.

10. Which one of the following resource is not necessarily required on a file server?
a) secondary storage
b) processor
c) network
d) monitor

Answer: d

Operating System Multiple Choice Questions on “The Fork and exec System Calls”.

1. Which of the following system calls does not return control to the calling point, on termination?
a) fork
b) exec
c) ioctl
d) longjmp

Answer: b

2. The following program results in the creation of?

   main()
   {
      if(fork()>0)
      sleep(100);
   }

a) an orphan process
b) a zombie process
c) a process that executes forever
d) none of the mentioned

Answer: b

3. Which of the following system calls transforms executable binary file into a process?
a) fork
b) exec
c) ioctl
d) longjmp

Answer: b

4. How many times the following C program prints yes?

 main()
   {
     fork();fork();printf("yes");
   }

a) only once
b) twice
c) four times
d) eight times

Answer: c

5. Which of the following calls never returns an error?
a) getpid
b) fork
c) ioctl
d) open

Answer: a
Clarification: None.

6. A fork system call will fail if ______________
a) the previously executed statement is also a fork call
b) the limit on the maximum number of processes in the system would be executed
c) the limit on the minimum number of processes that can be under execution by a single user would be executed
d) all of the mentioned

Answer: b
Clarification: None.

7. If a thread invokes the exec system call ____________
a) only the exec executes as a separate process
b) the program specified in the parameter to exec will replace the entire process
c) the exec is ignored as it is invoked by a thread
d) none of the mentioned

Answer: b
Clarification: None.

8. If exec is called immediately after forking ____________
a) the program specified in the parameter to exec will replace the entire process
b) all the threads will be duplicated
c) all the threads may be duplicated
d) none of the mentioned

Answer: a
Clarification: None.

9. If a process does not call exec after forking ____________
a) the program specified in the parameter to exec will replace the entire process
b) all the threads should be duplicated
c) all the threads should not be duplicated
d) none of the mentioned

Answer: b
Clarification: The new process is purely based on fork, due to no exec command, duplication will be done.