Command Line

Question 1

pwd

Answer 1

print working directory

Question 2

hostname

Answer 2

my computer’s network name

Question 3

mkdir

Answer 3

make directory

Question 4

cd

Answer 4

change directory

Question 5

ls

Answer 5

list directory

Question 6

rmdir

Answer 6

remove directory

Question 7

pushd

Answer 7

push directory

Question 8

popd

Answer 8

pop directory

Question 9

cp

Answer 9

copy file or directory

Question 10

mv

Answer 10

move file or directory

Question 11

less

Answer 11

page through a file

Question 12

cat

Answer 12

print the whole file

Question 13

xargs

Answer 13

execute arguments

Question 14

find

Answer 14

find files

Question 15

grep

Answer 15

find things inside files

Question 16

man

Answer 16

read a manual page

Question 17

apropos

Answer 17

find what man page is appropriate

Question 18

env

Answer 18

look at your environment

Question 19

echo

Answer 19

print some arguments

Question 20

export

Answer 20

export/set a new environment variable

Question 21

exit

Answer 21

exit the shell

Question 22

sudo

Answer 22

DANGER! become super user root DANGER!

Question 23

chmod

Answer 23

change permission modifiers

Question 24

chown

Answer 24

change ownership

Question 25

mkdir -p

Answer 25

will make an entire path even if all the directories don’t exist

Question 26

cp -r

Answer 26

command to copy more directories with files in them

Question 27

$|$

Answer 27

The | takes the output from the command on the left, and “pipes” it to the command on the right. In line 1 you see me do that.

Question 28

$<$

Answer 28

The < will take and send the input from the file on the right to the program on the left. You see me do that in line 2. This does not work in PowerShell.

Question 29

$>$

Answer 29

The > takes the output of the command on the left, then writes it to the file on the right.

Question 30

$»$

Answer 30

The&raquo_space; takes the output of the command on the left, then appends it to the file on the right.

Question 31

find STARTDIR -name WILDCARD -print

Answer 31

find STARTDIR -name WILDCARD -print