Linux Commands

Question 1

cd

Answer 1

change directory (without specifications changes to home automatically)

Question 2

hostname

Answer 2

displays system name

Question 3

TAB key

Answer 3

autocomplete as much of filename as system can

• if name has been completed, there will be a space after name
• press TAB again to display a list of possible completions

Question 4

TAB key + RETURN key

Answer 4

execute command (that was autocompleted)

Question 5

ls-l

Answer 5

determine file type

• hyphen infront of file listed = regular file
• b or C indicates a device file
• d indicates a directory file

ls commands can be combined!

Question 6

ls -ld

Answer 6

detailed listing command, get info on just directory files

Question 7

ls -a

Answer 7

show all files including hidden files

Question 8

ls -A

Answer 8

show Almost all files, not include . and .. files

Question 9

ls -F

Answer 9

displays / after directory, * after executable file

Question 10

pwd

Answer 10

print working directory

Question 11

cd directorypath

Answer 11

change to a directory

Question 12

mkdir directorypath

Answer 12

create a subdirectory with a directory

Question 13

mkdir -p

Answer 13

create parent directories and directories

Question 14

rmdir directorypath

Answer 14

removes empty directories

Question 15

mv sourcepath destinationpath

Answer 15

move file to a new location OR rename file OR moves directories

Question 16

mv -i

Answer 16

asks for confirmation if file already exists before moving

Question 17

lpr

Answer 17

put one or more file in que for printing

Question 18

lpr -P [insert printer name] [insert filename]

Answer 18

place file in que for specific printer

Question 19

lpstat -p

Answer 19

display list of available printers

Question 20

lpstat -o

Answer 20

view which jobs are in printer

Question 21

lprm

Answer 21

remove job from printer

Question 22

cp sourcepath destinationpath

Answer 22

copy file from one location to another, or backup important files

Question 23

cp -i

Answer 23

asks for confirmation if file already exists before copying

Question 24

cp -r

Answer 24

allows for copying of directories and their contents

Question 25

grep 'searchingfor' filename

Answer 25

search for 'string' in filename

Question 26

grep -w

Answer 26

search for only whole words

Question 27

head

Answer 27

displays beginning (first 10 lines) of file

Question 28

head -#

Answer 28

displays desired number of lines from beginning of file

Question 29

tail

Answer 29

displays the end (last 10 lines) of file

Question 30

tail -f filename

Answer 30

monitor lines as added to file | CONTROL + C to stop shell and display prompt

Question 31

sort

Answer 31

displays files in order (automatically alphabetical)

Question 32

sort -u

Answer 32

displays unique lines, no duplicates

Question 33

sort -n

Answer 33

lists of numbers in numerical order

Question 34

uniq

Answer 34

removes duplicate lines from a file

Question 35

diff

Answer 35

compare two files and display a list of the differences between them

Question 36

diff -u

Answer 36

displays two lines indicating which of the files are being compared with a plus sign (+) and a minus sign (-)

Question 37

rm filepath

Answer 37

remove regular file

Question 38

rm -r filepath

Answer 38

recursively remove directory and contents (this includes all subdirectories)

Question 39

rm -i

Answer 39

include confirm deletion of subdirectories and contents

Question 40

cat filepath

Answer 40

join files, shows contents of multiple files on screen

Question 41

more filepath

Answer 41

display contents of large regular files one screen at a time

Question 42

less filepath

Answer 42

same as more, just contains more navigation features

Question 43

touch path

Answer 43

update date and time of existing files OR create empty files

Question 44

find XXXX

Answer 44

find file

Question 45

find / -name bob

Answer 45

find filename containing "bob"

Question 46

find / -user alice

Answer 46

find filename with user "alice"

Question 47

find / name XXX -empty -delete

Answer 47

find, empty and delete file with name XXX

Question 48

find / -mmin

Answer 48

find files made within 5 minutes

Question 49

find / -size + 100M

Answer 49

find files over 100 MB

Question 50

man [options] command

Answer 50

access online manual related to "command"

Question 51

man -k command

Answer 51

provide short explanation relating to commands matching string. Used if user doesn't know name of command

Question 52

chmod ### filename

Answer 52

change permissions

Question 53

umask ### filename

Answer 53

change permissions

Question 54

rm -rf

Answer 54

remove files and directories recursively by force, even if they are protected from deletion

Question 55

chmod g+rw filename

Answer 55

add permissions

Question 56

chmod g-rw filename

Answer 56

remove permissions

Question 57

chmod g=rw filename

Answer 57

set permissions

Question 58

chmod u=rwx,g+x,o= .

Answer 58

combined

Question 59

sort -f

Answer 59

???

Question 60

grep -i

Answer 60

???