Linux

Question 1

Pwd

Answer 1

Present working directory

Question 2

What is this symbol: ~

Answer 2

Tilde

Question 3

What does the ~ sign expand to?

Answer 3

The full path for your home directory

Question 4

Why is understanding where you are at any given time in your file system important?

Answer 4

This information can help you build paths to other files or help you if you get lost.

Question 5

By default, Pwd will list the “logical” path of your current directory. What does this mean?

Answer 5

It will treat say linked paths as if they were the actual paths.

Question 6

If you want to see the actual physical path of the directory in which you are working, what flag can you use?

Answer 6

pwd -P

Question 7

What is the command for listing files and directories?

Answer 7

ls

Question 8

How do you find out what files are in another directory?

Answer 8

Pass a path to the ls command.

Question 9

It is common for Unix and Linux based machines to have ‘invisible’ or ‘hidden’ files that are prefixed with a ___.

Answer 9

‘dot’

Question 10

What flag can you use to see hidden files?

Answer 10

ls -a

Question 11

What is the flag for listing files and directories in long form?

Answer 11

ls -l

Question 12

What is symlink short for?

Answer 12

Symobolic link

Question 13

What flag can you use to see sizes of files in kilobytes and megabytes?

Answer 13

ls -lh

Question 14

What is the default method of sorting a list of files and directories?

Answer 14

By name

Question 15

How can we change the list function to sort by size (largest first)?

Answer 15

ls -lS

Question 16

What flag can we use to list files and directories by the last time they were modified?

Answer 16

ls -lt

Question 17

How can we reverse the sort of any of the sorting flags for the ls command?

Answer 17

-r

Question 18

What is the command for creating a link?

Answer 18

ln

Question 19

By default, the ln command will create a ____ link between files.

Answer 19

hard

Question 20

What happens when you create a hard link?

Answer 20

Hard links create an identical copy of the linked file on disk, which gets updated automatically as the source file gets updated.

Question 21

How do we create a link to a file using the ln command?

Answer 21

We call the ln command with two arguments - the first being the source file and the second being the target file.

Question 22

Can hard links connect two file systems?

Answer 22

No they only work on the current file system. Symbolic links can link to files on different file systems.

Question 23

If the source file of a hard link gets deleted, what will happen to the target file?

Answer 23

It will continue to live as an independent file, despite the severed link.

Question 24

If the file you are trying to link a file that already exists, you will get an error. How can you force the system to link the files anyway (deleting whatever you have saved in that file).

Answer 24

-f (force)

Question 25

Do hard links work for directories?

Answer 25

No, only symlinks

Question 26

How do we create a symlink?

Answer 26

ln -s

Question 27

Which of the kinds of links are more powerful and more common?

Answer 27

Symlinks

Question 28

How do you change directories?

Answer 28

cd

Question 29

What one argument does cd take?

Answer 29

The path to the directory you wish to naviagate to.

Question 30

What is the special path . . used for?

Answer 30

Moving to the current directories parent directory.

Question 31

What happens when you call cd without any arguments?

Answer 31

You will go back to the home directory.

Question 32

What command do you use to create new directories?

Answer 32

mkdir

Question 33

What flag can you use to make nested directories?

Answer 33

mkdir -p parent_file/sub_file/double_sub

Question 34

When would you use the -v flag?

Answer 34

Using the -v flag can provide useful reporting when writing scripts that will execute a lot of commands for you.

Question 35

What is the name of the -v flag?

Answer 35

Verbose Output