20250419

Question 1

What is the difference between single and double quotes for strings on Linux?

Answer 1

• Single quotes treat their contents literally, while double quotes permit varibles and other shell contents to be evaluated like the variable $HOME in a string

Question 2

What to do if a character has a special meaning to the shell

Answer 2

precede the character with the \ character
like echo a\* instead of echo a*
`echo “I live in a $HOME”

Question 3

How to display the last 4 previous commands in the shell?

Answer 3

history 4

Question 4

How to clear the history?

Answer 4

history -c

Question 5

What does !! represent?

Answer 5

your previous command

Question 6

What does represent the last argument from the previous command, and what is it used for?

Answer 6

!$

great for checking that files are present before running a destructive command
- ls z*
- rm !$

Question 7

What does !* represent?

Answer 7

Represents all arguments from the previous command
- ls check_imports.sh check_ql.sh
- wc !*