Environment & Redirection

Question 1

PushD

Answer 1

The pushd command takes your current directory and “pushes” it into a list for later, then it changes to another directory. It’s like saying, “Save where I am, then go here.
On Unix pushd, if you run it by itself with no arguments, will switch between your current directory and the last one you pushed.

Question 2

PopD

Answer 2

The popd command takes the last directory you pushed and “pops” it off, taking you back there.

Question 3

What is | ?

Answer 3

Piping. This moves the output of one process to the input of another process

Question 4

What is > or < ?

Answer 4

This redirects output of a process to replace the contents of a file

Question 5

What is&raquo_space; or &laquo_space; ?

Answer 5

This appends output of a process to an existing file

Question 6

echo $HOME

Answer 6

This calls to output the value of the variable HOME

Question 7

How do you set variables?

Answer 7

Don’t use $ sign. Just set it. PS1=”\u \w $”

Question 8

“Find?”

Answer 8

Find looks for file or folder names find . -name “hello.txt” MAN find for help

Question 9

“Grep?”

Answer 9

Looks for Global Regular expression Print. basically searches inside a file. -n lists the output’s line numbers. GREP is case sensitive. Just pass -i option to make case Insensitive. Pass -v option to INVERT or provide the negative outcome. MAN grep for help

Question 10

Apropos?

Answer 10

Apropos finds help similar to MAN