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QUESTION 2 You have finished your thesis, and want to set the permissions so tha

ID: 3826889 • Letter: Q

Question

QUESTION 2

You have finished your thesis, and want to set the permissions so that it is hard to accidentally delete or overwrite the file.

Normally, if you were to type "rm Thesis.txt", it would just delete it without asking. Or, if you moved a file with the same name into the same directory as your original Thesis.txt, it would overwrite it with the new version.

Which command would change the permissions for a file called Thesis.txt so that you are less likely to delete or overwrite it by accident?

chmod a+w Thesis.txt

chmod a-w Thesis.txt

chmod o-rwx Thesis.txt

chmod a+rwx Thesis.txt

QUESTION 5

Which of the following are true statements?

Unix filenames cannot contain spaces or punctuation characters

Unix filenames don't require extensions like .txt or .doc to determine the file type or purpose.

Unix filenames cannot be longer than 8 characters

Unix filenames are case sensitive, meaning that upper case a lowercase are treated differently

QUESTION 6

Which of the following commands uses sort as a filter?

ls > sort > tail

cat /etc/passwd | sort | head

sort /etc/passwd | more

ps ax | wc > sort

QUESTION 7

True or False? Unix does not have a graphical user interface, and can only be operated by entering text commands.

True

False

QUESTION 9

Which line of the following output is a symbolic link?

Line 1

Line 2

Line 3

Line 4

QUESTION 10

On debian-based systems, which command will list currently installed software packages?

dpkg -l

pkg --list

list-packages

apt-get -l

QUESTION 11

What is the numeric or Octal version of the following permissions for a file? -rw- r-- r--

Or, put a different way: u=rw,g=r,o=r

655

755

644

311

QUESTION 13

You asked your team to collect the serial numbers of all your equipment for insurance purposes. Unfortunately some members of the team visited the same rooms and you are certain that some of the lists they sent in contain the same serial numbers.

Assuming you have three text files of serial numbers named "serials-andy", "serials-mary", and "serials-pat", how would you remove all the duplicate serial numbers?

(You can verify your answer by creating three files with these names, puting some random numbers in them with some duplicates, and trying the commands)

uniq serials-* | sort

cat serials-* | sort | uniq

uniq serials-andy | uniq serials-mary | uniq serials-pat

sort serials* | uniq -d

QUESTION 14

When you type "ls /usr/bin" to view a detailed list of available unix programs, the list is longer than the screen so much of it scrolls by quickly. How would you use a pipe to view it one page at a time?

a.less | /usr/bin

b.ls | /usr/bin | less

c.ls /usr/bin | less

d.ls /usr/bin > less

QUESTION 16

In the vi text editor, which sequence of commands will copy the current line and past a copy of it below? (go ahead and try these to find out!)

"D" then "p"

"yy" then "p"

"C" then "p"

"c" then "v"

QUESTION 20

What is an advantage of compiled programs over interpreted programs?

Complied programs don't have security vulnerabilities.

compiled programs

Compiled programs are more portable across different operating systems.

Compiled programs are easier to check for errors.

a.

chmod a+w Thesis.txt

b.

chmod a-w Thesis.txt

c.

chmod o-rwx Thesis.txt

d.

chmod a+rwx Thesis.txt

QUESTION 5

Which of the following are true statements?

a.

Unix filenames cannot contain spaces or punctuation characters

b.

Unix filenames don't require extensions like .txt or .doc to determine the file type or purpose.

c.

Unix filenames cannot be longer than 8 characters

d.

Unix filenames are case sensitive, meaning that upper case a lowercase are treated differently

QUESTION 6

Which of the following commands uses sort as a filter?

a.

ls > sort > tail

b.

cat /etc/passwd | sort | head

c,

sort /etc/passwd | more

d.

ps ax | wc > sort

QUESTION 7

True or False? Unix does not have a graphical user interface, and can only be operated by entering text commands.

True

False

QUESTION 9

Which line of the following output is a symbolic link?

  Line 1: -rw-r--r--    1 wbackman  staff    640 May 16  2013 docproj_submitting.diff.txt  Line 2: lrwxr-xr-x    1 wbackman  staff     21 Jan 29 07:54 perf -> /var/log/performance/  Line 3:  -rw-r--r--    1 wbackman  staff  29837 Dec  3 15:07 simple-web-request-ipv6.pcap  Line 4:   -rw-r--r--    1 wbackman  staff    102 Jul 30  2013 start-tftp.sh  

Line 1

Line 2

Line 3

Line 4

QUESTION 10

On debian-based systems, which command will list currently installed software packages?

a.

dpkg -l

b.

pkg --list

c.

list-packages

d.

apt-get -l

QUESTION 11

What is the numeric or Octal version of the following permissions for a file? -rw- r-- r--

Or, put a different way: u=rw,g=r,o=r

a.

655

b.

755

c.

644

d.

311

QUESTION 13

You asked your team to collect the serial numbers of all your equipment for insurance purposes. Unfortunately some members of the team visited the same rooms and you are certain that some of the lists they sent in contain the same serial numbers.

Assuming you have three text files of serial numbers named "serials-andy", "serials-mary", and "serials-pat", how would you remove all the duplicate serial numbers?

(You can verify your answer by creating three files with these names, puting some random numbers in them with some duplicates, and trying the commands)

a,

uniq serials-* | sort

b.

cat serials-* | sort | uniq

c.

uniq serials-andy | uniq serials-mary | uniq serials-pat

d.

sort serials* | uniq -d

QUESTION 14

When you type "ls /usr/bin" to view a detailed list of available unix programs, the list is longer than the screen so much of it scrolls by quickly. How would you use a pipe to view it one page at a time?

a.less | /usr/bin

b.ls | /usr/bin | less

c.ls /usr/bin | less

d.ls /usr/bin > less

QUESTION 16

In the vi text editor, which sequence of commands will copy the current line and past a copy of it below? (go ahead and try these to find out!)

a.

"D" then "p"

b.

"yy" then "p"

c.

"C" then "p"

d.

"c" then "v"

QUESTION 20

What is an advantage of compiled programs over interpreted programs?

a.

Complied programs don't have security vulnerabilities.

b.

compiled programs

c.

Compiled programs are more portable across different operating systems.

d.

Compiled programs are easier to check for errors.

Explanation / Answer

Answers in bold

Q2 Normally, if you were to type "rm Thesis.txt", it would just delete it without asking. Or, if you moved a file with the same name into the same directory as your original Thesis.txt, it would overwrite it with the new version.

Which command would change the permissions for a file called Thesis.txt so that you are less likely to delete or overwrite it by accident?

chmod a+w Thesis.txt

chmod a-w Thesis.txt

chmod o-rwx Thesis.txt

chmod a+rwx Thesis.txt

QUESTION 5

Which of the following are true statements?

Unix filenames cannot contain spaces or punctuation characters

Unix filenames don't require extensions like .txt or .doc to determine the file type or purpose.

Unix filenames cannot be longer than 8 characters

Unix filenames are case sensitive, meaning that upper case a lowercase are treated differently

QUESTION 6

Which of the following commands uses sort as a filter?

ls > sort > tail

cat /etc/passwd | sort | head

sort /etc/passwd | more

ps ax | wc > sort

QUESTION 7

True or False? Unix does not have a graphical user interface, and can only be operated by entering text commands.

True

False

QUESTION 9

Which line of the following output is a symbolic link?

Line 1

Line 2

Line 3

Line 4

a.

chmod a+w Thesis.txt

b.

chmod a-w Thesis.txt

c.

chmod o-rwx Thesis.txt

d.

chmod a+rwx Thesis.txt