Topic 3: The power of the command line

Question 1

what command would you use to unpack this file: archive.tar?

Answer 1

tar xf archive.tar

Question 2

what two utilities could be used to print the contents of a file to the screen?

Answer 2

cat and less

Question 3

what is the format for a loop?

Answer 3

for i in { blank }; do echo $; done

Question 4

what is a valid if statement?

Answer 4

if [ blank ]; then echo $; fi

Question 5

what does an exit status of 1 indicate?

Answer 5

there was an error with the command

Question 6

what does an exit status of zero indicate?

Answer 6

the command ran successfully

Question 7

purpose of the command tar

Answer 7

create, update, list and extract archives. could also compress a group of files into an archive for backup

Question 8

4 popular tools for compression

Answer 8

gzip, bzip, xz, and zip

Question 9

what is the channel number for standard input?

Answer 9

channel zero

Question 10

what is the channel number for standard output?

Answer 10

channel 1

Question 11

what is the channel number for standard error?

Answer 11

channel 2

Question 12

what is a bit bucket and an example?

Answer 12

a file that accepts input and doesn’t do anything with it.
example: /dev/null folder

Question 13

what is the purpose of the command grep?

Answer 13

to search for a pattern or string

Question 14

purpose of the command less

Answer 14

print contents of a file to the screen like man pages. user can scroll up and down a line at a time