Linux

Question 1

Create a tree structure recursively

Answer 1

Mkdir -p ~/myFile/file/filenote

Question 2

How to make a file with out gedit

Answer 2

touch filename
Kate fileName
vi fileName (I to insert, shift zz to exit)
Leafpad

Question 3

All the ways to extract a bit of a file

Answer 3

sed -n 1~2p
-n line #; p print;
, inclusive range;

head

tail

Question 4

How to find info on a specific command

Answer 4

man

Question 5

Sort switches

Answer 5

sort -k 2d fileName

-k column #
2d column #\ data type
Column 2 alphanumeric
3n column 3 numerically

Question 6

What does the crontab do?

Answer 6

Enables you to regularly schedule reoccurring jobs.

crontab -e

Question 7

Join 2 files together column wise

Answer 7

Cat&raquo_space; ~/trials/file1
For typing what to add
Cat file1&raquo_space; file2
Joining 2 files

Question 8

Know about the calendar

Answer 8

cal 05 2017
05 month
2017 year
You can’t specify the day

Question 9

How to compress/ uncompress a file

Answer 9

Gzip -l file1
(To zip the file)
(Will give it a .gz)
gunzip file1.gz

Question 10

How to get the unique files out of a file

Answer 10

uniq file one
(To view)
uniq file1 > uniqFile1
(To take out)

Question 11

How to count stuff in a file

Answer 11

wc file1
(Just one file)
wc file1 file2 file3
(You can do more then one file at a time)

Question 12

What do the wild cards do

Answer 12

*0 or more matching chars in a fileName
?represents a single char
[] A range

Question 13

Absolute path and relative path

View the parent of:
/home/student/devices/routers/

Answer 13

Absolute:
ls /home/student/devices/

relative:
ls ..

Question 14

Create a link to the:

/home/student/inventory

Answer 14

ln -s /home/student/inventory /home/student/inventory.bak

Must use absolute path
To unlink:
unlink

Question 15

Understand the permissions

Answer 15

(-)[---]{---} 11
()file type
[]you
{}group
<>other 
11 # of hard links 
Directory, read, wright, execute, -file

Question 16

How to move files in the tree

Answer 16

mv ./file1/file2 ./file1/file3

Question 17

Remove a directory recursively

Answer 17

rm -rvi file1

Yes to all

Question 18

Change permissions symbolically

Answer 18

Chmod u+r+w+x,g+r+w,o+r file1

Question 19

Change permissions numerically

Answer 19

chmod 764 file1

4 read
2write
1 execute
0 fuck all

Question 20

Find file types

Answer 20

find -name "*a"/ "a*"
find -cmin 1
find -links 3
find -size 57c
find -type l, f, d
find -user student

Question 21

Make a new user and change there password

Answer 21

sudo useradd -m -d /home/user1 user1

Sudo passwd user1
sudo cat shadow

Question 22

Display environment variables

Answer 22

env

SHELL=/Bin/bash 
USER=student 
SUDO_COMMAND=/bin/bash 
PWD=/home 
HOME=/home/student
LOGNAME=student 
OLDPWD=/home/student

Question 23

What does the ~ and !~ operators mean

Answer 23

~ = matches 
!~ = does not match

Question 24

Joining 2 files together row wise

Answer 24

Paste -d file1 file2

Or to make a new file

Paste -d “ “ file1 file2 > file3

Question 25

What do pipes do?

Answer 25

The output of the last command becomes the input of the next command

Question 26

Assignment operators

Answer 26

Right hand side is evaluated and and assigned to the left hand side; assignHigh to a very low number one you do t expect to hit; assignLow to a really high number one you don’t expect to hit

Question 27

What is a relative path

Answer 27

Relative to the default directory

Question 28

What is absolute path

Answer 28

Resigns at and includes the system root

Question 29

What is a column and a row?

Answer 29

Column is a field

Row is a record

Question 30

Use the history list

Answer 30

history for just the 1000

history 5 to specify

Question 31

Scripting place holders

Answer 31

%d int
%f float
%s string

%8.2f

Question 32

What are the main ps switches

Answer 32

• a all
• A all system process
• al all in long format

Question 33

Proses 1 and 2

Answer 33

1 Init

2 Kthread

Question 34

Tar switches

Answer 34

Create 
Table of cont 
Xtract 
fileName 
Verbose 
Zip