OS quiz 3

1.

1 point

The correct seqeuence of procedures that a software programmer uses to create computer programs is

Source codes --> Link --> Compile --> Executable file.

Source codes --> Compile --> Link --> Executable file.

Compile --> Link --> Source codes --> Executable file.

Link --> Source codes ---> Compile ---> Executable file.

2.

1 point

Use the output of the following commands to answer the question below.
[student@station student]$ tail /etc/passwd
sleepy:x:507:507::/home/sleepy:/bin/bash
grumpy:x:509:509::/home/grumpy:/bin/bash
doc:x:510:510::/home/doc:/bin/bash
ventura:x:511:511::/home/ventura:/bin/bash
hogan:x:512:512::/home/hogan:/bin/bash
pataki:x:513:513::/home/pataki:/bin/bash
einstein:x:514:514::/home/einstein:/bin/bash
maxwell:x:515:515::/home/maxwell:/bin/bash
nero:x:516:516::/home/nero:/bin/bash
julius:x:517:517::/home/julius:/bin/bash
[student@station student]$ cat /etc/group
...
wrestle:x:201:ventura,hogan,elvis
physics:x:202:einstein,maxwell,elvis
emperors:x:203:nero,julius,elvis
governor:x:204:ventura,pataki
music:x:205:elvis,blondie,prince,madonna
dwarfs:x:206:sleepy,grumpy,doc
...
hogan:x:512:
pataki:x:513:
einstein:x:514:
maxwell:x:515:
nero:x:516:
julius:x:517:

Which group DOES contain the user ventura as a member?

ennervate

emperors

governor

physics

3.

1 point

Under which of the four application scenarios below are threads not useful?

We want to make the application more interactive and have better responsiveness.

We want to improve the performance of a server application by serving multiple requests at the same time.

We have an application that must run sequentially and cannot be parallelized due to certain constraints and dependencies.

We have an application that processes large amounts of data.

4.

1 point

Which of the following statements most accurately describes a process that is currently in the waiting (blocked) state?

The process is currently using the CPU at that instant.(running state)

The process is unable to run until some external event happens.

The process is runnable, but is waiting in a queue.

The process no longer has an entry in the process table.

5.

1 point

Which one of the following statements does not describe kernel threads in a typical operating system.

The kernel performs thread creation, scheduling and management in kernel space.

Blocking calls are handled by kernel, the kernel can schedule another thread in the application.

Kernel threads are slower to create to and manage that user threads.

The kernel relies on software libraries and routines to provide support for thread creation, scheduling and management.

6.

1 point

Which of the statements below is not true regarding scheduling in batch systems?

The memory scheduler determines which processes are kept in memory and which on the disk.

The process scheduler in a batch system consists of four different components, i.e. the routing scheduler, the admission scheduler, the memory scheduler and the CPU scheduler.

The admission scheduler decides which jobs to admit to the system.

The CPU scheduler picks one of the ready processes in main memory to run next.

7.

1 point

All the information about each process is stored in an operating system structure called the __________.

Process structure.

Process table.

Process memory.

Process link.

8.

1 point

The operating system has just loaded five processes, A, B, C, D, and E for execution. They have estimated running times of 1, 7, 3, 5 and 2 minutes. Their (externally determined) priorities are 3, 5, 2, 1 and 4, respectively, with 5 being the highest priority. If shortest job first (SJF) scheduling is used and a process is run until it finishes, what is the order that the scheduler will schedule the processes to run?

A --> B --> C --> D --> E

E --> D --> C --> B --> A

B --> E --> A --> C --> D

A --> E --> C --> D --> B

9.

1 point

Use the output of the following command to answer the following question.
[elvis@station elvis]$ ls -l
total 4
-rw------- 1 elvis elvis 138 May 8 16:15 diary.txt
Which of the following commands would result in diary.txt having permissions of rw-r--r--?

chmod o+rw diary.txt

chmod u-w diary.txt

chmod ugo+rw diary.txt

chmod ugo+r diary.txt

10.

1 point

Which of the following statements is not true about a program?

A program is an application written by software programmer and can be used by a normal user or a system administrator.

A program consists of one or more files.

Programs are stored inside secondary storage such as a hard disk, cd-rom or a floppy disk.

A program uses up main memory and CPU time.

11.

1 point

Which of the following items is shared by all threads running in a process?

Stack.

Address space.

Program counter.

Registers

12.

1 point

Maximizing throughput, reducing turnaround time and increasing CPU utilization are scheduling goals for __________.

Batch systems.

Interactive systems.

Real-time systems.

All of the above.

13.

1 point

Which of the following best explains why someone would want the file sample.sh to have permissions of rwxrwxr-x?

The owner would like anyone to be able to modify the file.

The owner would like anyone to be able to rename the file.

The owner would like anyone to be able to remove the file.

The owner would like anyone to be able execute the file as a script.

14.

1 point

Which permission represents the octal notation 701?

rwx-----x

x-----rwx

rwx---r--

r-----rwx

15.

1 point

A process that spends 80% of its time doing I/O wait is a __________ process.

CPU-bound

I/O-bound.

Process scheduling.

CPU utilization.

16.

1 point

The input to a compiler such as Visual Basic or Visual C++ is one or more __________ files.

Object code.

Static library.

Executable

Source code.

17.

1 point

Use the output of the following commands to answer the question below.
[student@station student]$ tail /etc/passwd
sleepy:x:507:507::/home/sleepy:/bin/bash
grumpy:x:509:509::/home/grumpy:/bin/bash
doc:x:510:510::/home/doc:/bin/bash
ventura:x:511:511::/home/ventura:/bin/bash
hogan:x:512:512::/home/hogan:/bin/bash
pataki:x:513:513::/home/pataki:/bin/bash
einstein:x:514:514::/home/einstein:/bin/bash
maxwell:x:515:515::/home/maxwell:/bin/bash
nero:x:516:516::/home/nero:/bin/bash
julius:x:517:517::/home/julius:/bin/bash
[student@station student]$ cat /etc/group
...
wrestle:x:201:ventura,hogan,elvis
physics:x:202:einstein,maxwell,elvis
emperors:x:203:nero,julius,elvis
governor:x:204:ventura,pataki
music:x:205:elvis,blondie,prince,madonna
dwarfs:x:206:sleepy,grumpy,doc
...
hogan:x:512:
pataki:x:513:
einstein:x:514:
maxwell:x:515:
nero:x:516:
julius:x:517:

Which of the following best explains why the group einstein has no members listed in the /etc/group file?

The file is misconfigured.

The group einstein is being used as a primary group, with no secondary group members.

einstein is a username only, and not a group name.

The group einstein has no members.

18.

1 point

A __________ scheduling algorithm picks a process and lets it run for a maximum of some fixed time. If it is still running at the end of time interval, it is suspended and the scheduler picks another process to run (if one is available).

Multi-tasking

Process

Non-preemptive.

Preemptive

19.

1 point

The operating system has just loaded five processes, A, B, C, D, and E for execution. The first process in the queue is A, followed by B, C, D and finally with E at the end of the queue. The processes have estimated running times of 1, 7, 3, 5 and 2 minutes. If non-preemptive first-come, first-served (FCFS) scheduling is used, what is the order that the scheduler will schedule the processes to run?

B --> E --> A --> C --> D

A --> B --> C --> D --> E

D --> C --> A --> E --> B

E --> D --> C --> B --> A

20.

1 point

Which file(s) must be consulted to determine the group name of a user's primary group?

/etc/shadow

/etc/passwd

Both A and C

/etc/group

21.

1 point

Which of the following statements is not true about a process?

Processes use up main memory and CPU time.

A process is created by software programmers.

Each process has its process space, which is a list of memory locations from some minimum to maximum, which the process can read or write.

A process is basically a program in execution. In other words, it is a running program.

22.

1 point

Which of the following commands could be used to start a new shell with the primary group music?

newgrp music

newgroup music

newgrp -g music

newgroup -G music

23.

1 point

If a process had a umask of 077, what would be the default permissions for newly created directories?

r--r--r--

rwx------

rw-rw-r--

rw-------

24.

1 point

Which of the following commands, along with root's password, would allow a user to start a shell as root?

switchuser root

su -

su - superuser

superuser -

25.

1 point

The specific technique or method which an operating system uses to decide which process gets to use the CPU is called the __________.

Process scheduler.

Program loader.

Interprocess communications.

Scheduling algorithm.

26.

1 point

Which of the following statements below is not true about a thread?

Threads are the entities scheduled for execution on the CPU.

One or more processes run inside a thread.

Threads are mini-versions of processes and are sometimes called lightweight processes.

Each thread will have its own private items which are its program counter, its register contents, its stack and its state.

27.

1 point

Which of the following statements below is not true about a thread?

Threads are mini-versions of processes and are sometimes called lightweight processes.

One or more processes run inside a thread.

Each thread will have its own private items which are its program counter, its register contents, its stack and its state.

Threads are the entities scheduled for execution on the CPU.

28.

1 point

Which of the following commands is used to change the group owner of a file?

group

chgrp

chgroup

changegroup

29.

1 point

Which of the following best describes why the /etc/passwd file is inappropriately named?

That's not how you spell password.

The file would more appropriately be stored in a user's home directory.

On most modern Linux and Unix systems, the file does not contain passwords.

The filename is too difficult to remember.

30.

1 point

Use the output from the following command to answer the following question.
[student@station grps]$ ls -l
total 16
-rw-rw---- 1 ventura wrestle 2027 May 9 07:38 antics
-rw------- 1 ventura ventura 126 May 9 07:40 donors
-rw-rw-r-- 1 madonna madonna 138 May 9 07:38 playlist
-rw-rw-r-- 1 ventura wrestle 29 May 9 07:38 slogans
The user ventura wants members of the group wrestle to be able to read his slogans, and everyone else to have no access to the file. What steps must he perform?

chmod g+w slogans

chgrp wrestle slogans

chmod o-r slogans

A and B

31.

1 point

Use the output of the following commands to answer the question below.
[student@station student]$ tail /etc/passwd
sleepy:x:507:507::/home/sleepy:/bin/bash
grumpy:x:509:509::/home/grumpy:/bin/bash
doc:x:510:510::/home/doc:/bin/bash
ventura:x:511:511::/home/ventura:/bin/bash
hogan:x:512:512::/home/hogan:/bin/bash
pataki:x:513:513::/home/pataki:/bin/bash
einstein:x:514:514::/home/einstein:/bin/bash
maxwell:x:515:515::/home/maxwell:/bin/bash
nero:x:516:516::/home/nero:/bin/bash
julius:x:517:517::/home/julius:/bin/bash
[student@station student]$ cat /etc/group
...
wrestle:x:201:ventura,hogan,elvis
physics:x:202:einstein,maxwell,elvis
emperors:x:203:nero,julius,elvis
governor:x:204:ventura,pataki
music:x:205:elvis,blondie,prince,madonna
dwarfs:x:206:sleepy,grumpy,doc
...
hogan:x:512:
pataki:x:513:
einstein:x:514:
maxwell:x:515:
nero:x:516:
julius:x:517:

What is the name of the user ventura's primary group?

The name of the user ventura's primary group cannot be determined from the information provided.

wrestle

ventura

governor

32.

1 point

Use the output from the following command to answer the following question.
[student@station grps]$ ls -l
total 16
-rw-rw---- 1 ventura wrestle 2027 May 9 07:38 antics
-rw------- 1 ventura ventura 126 May 9 07:40 donors
-rw-rw-r-- 1 madonna madonna 138 May 9 07:38 playlist
-rw-rw-r-- 1 ventura wrestle 29 May 9 07:38 slogans
Which users on the system can modify the permissions on the file slogans?

any valid user on the system

madonna

all members of the group wrestle

all members of the group music

33.

1 point

Meeting deadlines and having predictable performance are scheduling goals for __________.

Batch systems.

Interactive systems.

Real-time systems.

All of the above.

34.

1 point

Which of the following would be the most reasonable permissions for a directory that members of only a particularly group should have access to?

740

750

700

075

35.

1 point

Which of the following information is not associated with a uid in the user information database?

login terminal

login shell

username

home directory

36.

1 point

Which of the following would be the most reasonable permissions for a file that all users can read, but only the owner can write?

006

660

644

622

37.

1 point

Which of the following is true about the file /etc/shadow?

Standard users may view /etc/shadow file.

None of the above.

Both A and B

Standard users may edit /etc/shadow file.

38.

1 point

Use the output from the following command to answer the following question.
[student@station grps]$ ls -l
total 16
-rw-rw---- 1 ventura wrestle 2027 May 9 07:38 antics
-rw------- 1 ventura ventura 126 May 9 07:40 donors
-rw-rw-r-- 1 madonna madonna 138 May 9 07:38 playlist
-rw-rw-r-- 1 ventura wrestle 29 May 9 07:38 slogans
The user madonna wants members of the group music to be able to read and modify her playlist, and everyone else to only be able to read it. What steps must she perform?

chgrp music playlist

chown music playlist

A, then C

chmod g+w playlis

39.

1 point

Which of the following items is shared by all threads running in a process?

Registers.

Address space.

Stack

Program counter.