Terminal Tips and Tricks For Mac OS X

Question

One tip or trick per answer.

My favorite is

open .

Opens the folder you're currently browsing in Finder. You can also pass URLs, images, documents or else to open.

If you specify a program name with -a you can pass the URL, image, document or folder to that program instead, e.g. open -a Preview image.png, overriding the default program set for the filetype.

Mac OS X specific answers only.

Answer 1

pbcopy and pbpaste:

# Copy output of command to clipboard
grep 'search term' largeFile.txt | pbcopy

# Abuse clipboard contents
pbpaste | sed 's/ /%20/g'

Answer 2

It's not built in but this is the most effective way to get my wife to stop using my laptop to read celebrity news for hours after 4-5 requests to get my macbook back:

echo 'The system is overheating and needs to go to sleep now.' | \
growlnotify -a 'Activity Monitor' 'OVERHEATED'; \
sleep 1; \
say 'Overheated system.'

Since it's almost always around 70c it's believable.

Answer 3

opensnoop is my new favorite utility. It uses DTrace to show you all of the files that are being accessed on your system, you need to execute it with superuser privileges

sudo opensnoop

You can also watch what a particular process opens by passing in the PID:

sudo opensnoop -p PID

Or watch a particular file to see who's opening it

sudo opensnoop -f /etc/passwd

Answer 4

!!

Runs the last command again. Great for tracking changes.

Answer 5

The say command invokes the system text-to-speech capabilities.

say "Hello there."

Answer 6

mdfind to use spotlight from the command line - really really really handy! Finds things in every directory as well, so it's more useful when looking for files that are part of the system.

mdfind -live updates in real time, which again is incredibly handy.

Answer 7

Open a man page in Preview:

pman () {
    man -t "${1}" | open -f -a /Applications/Preview.app
}

Open a man page in TextMate:

tman () {
  MANWIDTH=160 MANPAGER='col -bx' man $@ | mate
}

Quit an app cleanly from the command line

# Quit an OS X application from the command line
quit () {
    for app in $*; do
        osascript -e 'quit app "'$app'"'
    done
}

Relaunch an app from the command line:

relaunch () {
    for app in $*; do
        osascript -e 'quit app "'$app'"';
        sleep 2;
        open -a $app
    done
}

Uninstall an app with AppZapper from the command line:

zap () {
    open -a AppZapper /Applications/"${1}".app
}

Answer 8

When you're editing a particularly long and gnarly command line ^X^E (Ctrl-X Ctrl-E) will pop you into your editor and let you work on it there.

Answer 9

Start a quick webserver from any directory:

python -m SimpleHTTPServer 8000

Answer 10

cd -

Will restore the previous directory you were in. Very handy if you accidentally type cd and flip to home.

Answer 11

(Assuming we're looking for Mac OS X specific tricks.)

I've got an alias to launch quicklook on a file from the command line:

$ type -a ql
ql is aliased to `qlmanage -p 2>/dev/null'
$ ql photo.jpg
Testing Quick Look preview with files:
    photo.jpg

Hit CtrlC to kill it and return to the prompt.

Answer 12

you can hit ctrl-a and ctrl-e to go to the beginning of the line and to the end of the line. This also works in every Cocoa text input!

Answer 13

afconvert allows you to convert from and to all audio formats internally known to Core Audio.

e.g., converting an aiff file to 160kbps AAC:

afconvert track.aiff -o track.m4a -q 127 -b 160000 -f 'm4af' -d 'aac '

Answer 14

You can drag a folder from the finder to the terminal and it will paste the full path to that file.

cd <drag folder to terminal> 

This is basically the opposite of open in the terminal

Answer 15

$ emacs -batch -l dunnet

Dead end
You are at a dead end of a dirt road.  The road goes to the east.
In the distance you can see that it will eventually fork off.  The
trees here are very tall royal palms, and they are spaced equidistant
from each other.
There is a shovel here.
>

Answer 16

Quickly check what is eating all your memory:

top -o vsize

And for your CPU

top -o cpu

Q to quit

Answer 17

With hdiutil you can easilly mount a disk image:

hdiutil mount ~/Desktop/lastest_webkit.dmg

Dismounting (hacker way):

hdiutil detach `df | grep WebKit | perl -pe 's@^/dev/([a-zA-Z0-9]+).*@$1@'`

Dismounting (easy way):

hdiutil detach /Volumes/<mountpoint>

or take the easier approach (that churnd suggested below):

hdiutil detach /Volumes/latest_webkit

Answer 18

Make files invisible:

SetFile file -a V

SetFile can change a lot of other file attributes and metadata, as well.

Answer 19

Here's something nice and pointless.

/System/Library/Frameworks/ScreenSaver.framework/Resources/ScreenSaverEngine.app/Contents/MacOS/ScreenSaverEngine -background &

Runs your screensaver as your desktop wallpaper. Useless but cool :)

Answer 20

To make Ctrl← and Ctrl→ useful again, that is going a word forward or backward like they usually do on Linux, you must make Terminal.app send the right string to the shell. In the preferences, go to the Settings tab and select your default profile. Go to Keyboard and set control cursor left and control cursor right to send string \033b and \033f respectively.

While your're at it, you can also fix Home (\033[H), End (\033[F), Page Up (\033[5~) and Page Down (\033[6~) so that they send those keys to the shell instead of scrolling the buffer.

Answer 21

Stop using the arrow keys and navigate the command line more quickly with

Ctrl-a moves to the start of the line

Ctrl-e moves to the end of the line

Ctrl-b move back on character

Ctrl-f move forward one character

Esc-b move back one word

Esc-f move forward one word

Ctrl-u delete from the cursor to the beginning of the line

Ctrl-k delete from the cursor to the end of the line

Answer 22

textutil is a very handy tool that can cross convert text between HTML, RTF(D), Word (including XML), OpenOffice.org Writer, and the webarchive format.

I use it, notably, in a service that converts the selected text to HTML, uploads it to a server then imports it into Instapaper.

Answer 23

You can hold option and click a position in the current line to move your cursor to that position.

Answer 24

Although I can get around in vi, I use TextMate as my command line editor. You can also pipe things to it. For example ls|mate opens up TextMate with the current directly listing open in a text window.

Answer 25

http://github.com/joelthelion/autojump - "cd" that learns.

Answer 26

mdls will show you all metadata of the file that Spotlight knows about. You can use the resulting attributes in "mdfind" as well.

mdutil allows you to switch indexing on or off on certain volumes, and allows you to reset the index etc.

systemsetup is BSD specific (not Mac only), but cool indeed, check its manpage.

GetFileInfo (I believe you have to get the developer tools in order to have this) allows you to see all associated times (modification, creation, last accessed) and all attributes of a file.

automator allows you to run automator workflows from the command line, while

osascript lets you run Apple script code.

Answer 27

bcat is a convenient pipe between my always-open terminal (xterm under XQuartz) and my always-open browser.

it sets up a streaming HTTP server for just one process so things like

tar czvf - . | tee bcat

will just stream until the command exits. Man pages need a bit of cleanup:

man bash | col -b | bcat

or just

export MANPAGER='col -b | bcat'
man bash

Answer 28

Hit and hold Esc a few seconds to get a list of every possible terminal command on your system, including built-ins, programs on your path, and aliases.

Or, as Martinj pointed out:

Just use TAB instead, you don't need to hold it for a few seconds even. TAB will also complete partially typed commands for you, as well as filenames and command-specific arguments.

A prompt asking if you really want to display all command possibilities will appear. Just answer y to get the command list.

Answer 29

diskutil is a very powerful command-line tool for working with disks and disk images. It's gotten me out of some binds. It's not too hard to use.

Answer 30

I’m not sure; this might work in any decent terminal application, not only in OS X’s. However:

Using Terminal.app it is possible to put status information to the actual title bar and not just to the prompt.

In order to do that, you need to change the PS1 variable in bash to the following model:

PS1='\[\033]0;TITLE\007\]PROMPT'

Where TITLE and PROMPT must be substituted to the actual commands which provide the status information. For example, \w lists the current full path; \W the directory name. You can even execute a command by putting it in backticks. (So you could even put the output of arbitrary commands to the title – or to the prompt.)

Git users (with git’s bash completion installed) might find the following useful. Add this to your .bashrc

export GIT_PS1_SHOWDIRTYSTATE=1
PS1='\[\033]0;`__git_ps1` \w\007\]\h:\W \u\$ '

and the title bar of Terminal.app will show the current git branch (and whether it’s clean or not) followed by the current full path. This gives useful information about where you are only when you need it and does not make the actual prompt overly long.

In case you don’t use git very much and only care about the path in the title bar:

PS1='\[\033]0;\w\007\]\h:\W \u\$ '