Command Line

Front 1

pwd

Back 1

print working directory

"directory" is just a folder

/Users/Lisa

Front 2

hostname

Back 2

my computer's network name

Lisas-MacBook-Air.local

Front 3

mkdir

Back 3

make directory

"path" = directories inside directories

mkdir -p i/like/icecream = makes the entire path

Front 4

cd

Back 4

change directory

can only cd down the path, not up

"cd .." to move up; "cd ../../.." to move up x3

"cd temp/stuff/things" to cd x3

just "cd" --> home directory

cd ~ = home directory, e.g. cd ~/folder/

Front 5

ls

Back 5

list directory = shows contents of that directory

ls -l = long listing

ls -a = listing including hidden files

ls -lh = long listing with human readable file sizes

ls - R --> shows ALL contents, not just 1 lvl

Front 6

rmdir

Back 6

remove directory

rmdir -p i/like/icecream = removes entire path

rm -rf newplace = removes directory and files w/i

Front 7

pushd

Back 7

push directory

--if in temp & pushd i/like, saves spot @ temp, goes to like

--pushd (with nothing more) will then toggle b/t temp and like

--popd sends you back to temp & unsaves the spot

Front 8

popd

Back 8

pop directory

--if in temp & pushd i/like, saves spot @ temp, goes to like

--pushd (with nothing more) will then toggle b/t temp and like

--popd sends you back to temp & unsaves the spot

Front 9

touch

Back 9

creates an empty file

changes time on file

Front 10

cp

Back 10

copy a file or directory

--cp iamcool.txt neat.txt = copies into same directory

--cp neat.txt something/ = copies neat.txt into something directory

--cp -r something newplace = creates copy of something directory named newplace

--overwrites files that already exist

Front 11

mv

Back 11

move a file or directory

--seems more like renaming

--mv awesome.txt uncool.txt = "moves" file to new path

--mv uncool.txt something/ = moves file to something directory

Front 12

less

Back 12

"page" through a file

--spacebar goes to next "page"

--w goes to previous "page"

--"q" to quit less

--once you quit the text WON'T show in terminal

Front 13

more

Back 13

Output content delivered in screensize chunks

"page" through a file, spacebar goes to next "page"

--"q" to quit more

--once you quit the text WILL show in terminal

Front 14

cat

Back 14

print the whole file

--doesn't "page"

--cat > somefile.txt = lets you type the text of the file directly in terminal, CTRL-D (on its own line) to end

Front 15

rm

Back 15

remove a file

--rm uncool.txt

--rm iamcool.txt neat.txt thefourthfile.txt--rm something/awesome.txt

--rmdir something

--rm -r [dir] = remove directory & contents

--rm -i [file] = remove w/confirmation

--rm -f [file] = force removal w/o confirmation

Front 16

|

Back 16

pipe

takes the output from the command on the left, and "pipes" it to the command on the right

Front 17

<

Back 17

will take and send the input from the file on the right to the program on the left

tell command to read content from a file

Front 18

>

Back 18

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

--cat ex13.txt > ex15.txt = creates ex15.txt file with text from ex13.txt

> [file] = Push output to file, keep in mind it will get overwritten

Front 19

>>

Back 19

takes the output of the command on the left, then appends it to the file on the right

>> [file] = append output to existing file

Front 20

*

Back 20

anything

-wherever *, the shell will build a list w/files that match the non-* part

-ls *.txt = anything ending in .txt

Front 21

find

Back 21

find files

--find . -name "*.txt" -print | less = find all .txt files

--"Hey find, start here (.) then find files named *.txt and print them".

--"find STARTDIR -name WILDCARD -print"

--find temp2 -name "*.txt" -print | less

Front 22

grep

Back 22

find things inside files

$ cat > newfile.txt

---This is a new file.

$ cat > oldfile.txt

---This is a old file.

$ grep new *.txt

---newfile.txt:This is a new file.

$ grep old *.txt

---oldfile.txt:This is a old file.

$ grep file *.txt

---newfile.txt:This is a new file.

---oldfile.txt:This is a old file.

Front 23

-i

Back 23

ignore case

--grep -i new *.txt

Front 24

man [command]

Back 24

read manual page for [command]

Front 25

apropos

Back 25

searches through man pages to find what man page is appropriate

Front 26

env

Back 26

look at your environment

Front 27

echo

Back 27

print some arguments

echo $TESTING

1 2 3

Front 28

export

Back 28

export/set a new environment variable

$ export TESTING="1 2 3"

$ echo $TESTING

1 2 3

Front 29

unset

Back 29

Unsave a variable

Front 30

exit

Back 30

exit the shell

Front 31

xargs

Back 31

execute arguments

Front 32

sudo

Back 32

DANGER! become super user root DANGER!

Run command with the security privileges of the superuser (Super User DO)

Front 33

chmod

Back 33

change permission modifiers

Front 34

chown

Back 34

change ownership

Front 35

CTRL-C

Back 35

abort command

Front 36

open [file]

Back 36

Opens a file ( as if you double clicked it )

Front 37

top

Back 37

Displays active processes. Press q to quit

Front 38

q

Back 38

Exit

Front 39

clear

Back 39

Clear screen

Front 40

history n

Back 40

Shows the stuff typed – add a number to limit the last n items

Front 41

ctrl-r

Back 41

Interactively search through previously typed commands

Front 42

![value]

Back 42

Execute the last command typed that starts with ‘value’

Front 43

!!

Back 43

Execute the last command typed

Front 44

[command] -h

[command] -- help

[command] help

Back 44

Offers help

Front 45

reset

Back 45

Resets the terminal display

Front 46

whatis [command]

Back 46

Gives a one-line description of [command]