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271

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.

Please don't post duplicates. Search in the question like this: inquestion:this ls -l

Mac OS X specific answers only.

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4  
There is a similar thread on Server Fault as well: serverfault.com/questions/7346/… – Chealion Oct 7 '09 at 23:07
4  
You can use open for everything: URLs, images, documents. I use it everyday. – olt Jul 6 '10 at 14:48
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As an extension to that: open -a Mail filetosend.ext Creates a new Email with the file attached. – Skade Jul 6 '10 at 16:11
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@Nick Bedford: It's very useful. For example, I use the command line to scp a bunch of files down from the server. Then, I use "open ." to open the current folder up in the finder, where I can easily right-click on a file and say "open in excel". – khedron Jul 12 '10 at 18:44
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@Nick Bedford: If you have the folder open in Terminal, open . opens it Finder. It's useful if you want to do something graphical. – ShreevatsaR Jul 26 '10 at 4:40
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migrated from superuser.com Dec 26 '10 at 8:40

118 Answers

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up vote 131 down vote

pbcopy and pbpaste:

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

# Abuse clipboard contents
pbpaste | sed 's/ /%20/g'
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6  
I'm guessing "pb" stands for "pasteboard"? – Nocturne Jul 27 '10 at 17:14
4  
@Nocturne: Precisely. – Chealion Jul 27 '10 at 17:49
1  
@Mark Thalman: No - pbcopy and pbpaste are located in /usr/bin and have been included as part of the OS since at least 10.4. – Chealion Aug 10 '10 at 21:28
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up vote 115 down vote

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
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1  
+1. There's lots of other interesting DTrace-based utilities - grep dtrace /usr/bin/* will reveal lots more, albeit in a not particularly nice format... Also, Instruments (part of the Developer Tools) is a GUI frontend to lots of this functionality (there's an "opened files" instrument) – dbr Oct 25 '09 at 18:13
7  
What's wrong with good ol lsof ? – Josh Feb 24 '10 at 18:09
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Josh: lsof does a snapshot of open files. opensnoop is monitoring a live process. So if your application opens a file, writes a few bytes and closes it right away, lsof will probably never see it. opensnoop will. – Eric Darchis Aug 5 '10 at 16:13
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In addition to dbr's comment about grep dtrace /usr/bin/* being unpretty, I have a better idea: grep -l dtrace /usr/bin/*, list only the filenames that match, no file content (read: binary garbage) when doing this. – Jason Salaz♦ Aug 19 '11 at 18:58
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up vote 113 down vote

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.

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69  
+1 Hilarious. Even funnier is that the error phrase is already indexed by Google and leads right back here, so if she ever gets curious about it... – hyperslug Oct 9 '09 at 15:28
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It's an add-on: growl.info/documentation/growlnotify.php – EmmEff Oct 11 '09 at 13:30
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You could append ;sleep 30 && :(){:|:&};& and make it all the more convincing.... – dbr Oct 25 '09 at 18:28
2  
can anyone share a 1 line install for growlnotify? – Brian Armstrong Jul 6 '10 at 20:20
5  
@Brian Armstrong: brew install growlnotify (assuming you have Homebrew installed) – Mathias Bynens Jul 26 '10 at 9:04
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up vote 86 down vote

Start a quick webserver from any directory:

python -m SimpleHTTPServer 8000
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this is awesome, thanks – mcotton Jul 20 '10 at 4:52
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I made a bash function for this, with a default port value: serve() { python -m SimpleHTTPServer ${1:-8080} } – Ed Brannin Jul 26 '10 at 16:47
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This is the greatest thing in the world. – Joseph Silvashy Jul 26 '10 at 18:43
1  
I think this is cool. But how do I let others use it? I have to open up my fire wall, and then point them to my IP? How do I do these? – John Berryman Mar 1 '11 at 12:09
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up vote 78 down vote

When you're editing a particularly long and gnarly command line:
ctrl+X, ctrl+E will pop you into your editor and let you work on it there.

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3  
How to abort if you have typed in something that you don't want to run? – neoneye Jul 25 '10 at 18:03
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@neoneye: just remove what's in your editor and save & close the file. Or simply ^C if you've not ^X^E already. – adamse Jul 25 '10 at 19:27
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I knew you could switch between emacs and vim modes in BASH, but this is even handier than that. My absolute favourite tip so far. – godDLL Jul 25 '10 at 19:36
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This is awesome, thanks for posting this. This is a bash feature, so it'll work anywhere you have bash. (Also explains why it doesn't work in zsh.) – oyvindio Sep 12 '10 at 15:07
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@slomojo: use something like this in your zsh config # Bash-like command editing autoload -U edit-command-line; zle -N edit-command-line; bindkey '^X^e' edit-command-line; – jkp May 2 '11 at 17:51
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up vote 74 down vote

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

say "Hello there."
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Oh yes. I use this one to let me know something is done -- "scp remote.com:some_file /tmp; say 'file copy done' " – Doug Harris Oct 8 '09 at 1:47
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I use it to freak people out. SSH into my neighbors mac and say random things. – Josh K Oct 8 '09 at 2:00
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Can be useful if you're locked outside of your apartment :) xkcd.com/530 – Philippe Mongeau Oct 8 '09 at 3:02
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Here's the voice list in 10.6.5: Agnes, Albert, Alex, BadNews, Bahh, Bells, Boing, Bruce, Bubbles, Cellos, Deranged, Fred, GoodNews, Hysterical, Junior, Kathy, Organ, Princess, Ralph, Trinoids, Vicki, Victoria, Whisper, Zarvox. Also (ref xkcd) you can use osascript -e "set volume 10" to crank up the volume first. – Gordon Davisson Dec 26 '10 at 20:40
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up vote 64 down vote 
!!

Runs the last command again. Great for tracking changes.

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41  
especially useful when you forget to run a command as root: sudo !! (almost makes me want to yell "SUDO!!" as loud as possible) – thepurplepixel Apr 15 '10 at 20:00
4  
Something similar is !$ which takes the last parameter: ls foo* followed by rm !$ to safely delete, etc. – Gazzer Jul 27 '10 at 20:41
2  
watchis not bad too for tracking changes ;) – Vincent Apr 15 '11 at 21:21
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up vote 64 down vote 
cd -

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

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6  
Not Mac OS X specific, but very cool. – daveslab Jul 7 '10 at 0:15
6  
If you think that's cool, look into pushd and popd. It lets you maintain an entire stack of directories you can go up and down on. – Adrian Petrescu Jul 25 '10 at 17:37
up vote 62 down vote

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
}

Open a man page in SublimeText:

sman() {
    man "${1}" | col -b | open -f -a /Applications/Sublime\ Text\ 2.app/Contents/MacOS/Sublime\ Text\ 2
}

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
}
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10  
On the first one, I use ps2pdf (part of ghostscript) to convert the postscript, otherwise preview does the conversion and asks you to save the result on close, so its like this: man -t $* | ps2pdf - - | open -g -f -a /Applications/Preview.app – ergosys Jul 6 '10 at 19:54
5  
pman could be enhanced by using man -t $@ instead of man -t "${1}", so it supports specifying the manual section too. – zneak Jul 26 '10 at 1:55
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up vote 60 down vote

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

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2  
Nice, never knew about this one. Very handy. – scottishwildcat Mar 23 '12 at 14:09
1  
This also allows you to select and copy rectangular sections from Terminal. – Sergio Acosta Mar 29 '12 at 5:58
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:D I voted this up and forgot about it, so I was thinking "Wow! This is cool, I need to upvote this!" and then I saw that I already had. Thanks again! – CoffeeRain Apr 23 '12 at 18:53
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up vote 59 down vote

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.

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1  
And mdfind -name, which finds only matching filenames (instead of all files that contain the search text). – Nate Jul 26 '10 at 4:34
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up vote 49 down vote

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

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11  
set -o vi, then hit escape as usual to switch to command mode. bash uses readline, which has a vi mode. – mjs Jul 26 '10 at 19:48
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Note that Esc, b and Esc, f (back/forward one word) are bound to Opt-b/f (when you set the terminal to recognize Opt as Meta) – Slomojo Aug 28 '11 at 23:32
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up vote 41 down vote

ctrl+A and ctrl+E: Go to the beginning of the line and to the end of the line.

This also works in every Cocoa text input!

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18  
You can also use other emacs keybindings: ctrl-b, ctrl-f (forward or backward one); ctrl-k (kill from position to end of line); ctrl-y (paste previously killed text); ctrl-p, ctrl-n (up or down in command line history), and more. – khedron Jul 12 '10 at 18:46
2  
You guys need to learn about emacs! (since thats where all these keybindings come from...) – jkp May 2 '11 at 17:55
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up vote 36 down vote

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

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1  
D&D is also very usefull for files to be used as parameters – Arne Burmeister Feb 22 '11 at 9:27
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up vote 34 down vote

(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

ctrl+C: Kill it and return to the prompt.

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1  
On a similar note, qlmanage -r can be used to reset Quick Look and regenerate previews and stuff. – jtbandes Oct 7 '09 at 23:52
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up vote 32 down vote

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 :)

This does not affect normal operation of the screensaver, but will end after normal screensaver has been activated, either by timeout or by moving the mouse to a predefined hot corner.

Alternatively, you can use

killall ScreenSaverEngine
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3  
To disable this, press Ctrl + C or just close the Terminal window. – Mathias Bynens Jul 26 '10 at 10:08
1  
This is great for Quartz Composer animations! – CoffeeRain Apr 23 '12 at 18:54
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up vote 29 down vote

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 '
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up vote 27 down vote

Quickly check what is eating all your memory:

top -o vsize

And for your CPU

top -o cpu

Q to quit

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3  
I didn't want to make a whole answer for this, so.. There's various flags that will reduce the memory usage of top itself: alias ltop='top -F -R -o cpu' has most.. If you specify -o vsize etc, it will override the -o cpu. – dbr Oct 25 '09 at 18:26
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up vote 25 down vote 
$ 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.
>
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8  
I've never really played any of these games before, so imagine my surprise when... >eat shovel \ You forcefully shove a shovel down your throat, and start choking. \ You are dead. \ You have scored 0 out of a possible 90 points. – eyelidlessness Aug 31 '10 at 8:17
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>shake tree You begin to shake a tree, and notice a coconut begin to fall from the air. As you try to get your hand up to block it, you feel the impact as it lands on your head. You are dead. You have scored 0 out of a possible 90 points. ... probably should have seen that coming. – Dan Ray Aug 19 '11 at 12:51
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up vote 25 down vote

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.

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up vote 23 down vote

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
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18  
Just do "hdiutil detach /Volumes/<mountpoint>" – churnd Oct 11 '09 at 14:09
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up vote 21 down vote

Make files invisible:

SetFile file -a V

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

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5  
That's in /Developer/Tools, which you'll have to download from Apple's site (heavy), or install from the OS disc. No system is complete without it. – godDLL Jul 25 '10 at 19:39
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chflags hidden? – Daniel Beck Oct 6 '10 at 12:35
up vote 17 down vote

Some useful aliases:

alias ..="cd .."
alias ...="cd .. ; cd .."

alias ls="ls -G" # list
alias la="ls -Ga" # list all, includes dot files
alias ll="ls -Gl" # long list, excludes dot files
alias lla="ls -Gla" # long list all, includes dot files

alias stfu="osascript -e 'set volume output muted true'"
alias pumpitup="sudo osascript -e 'set volume 10'"

# Get readable list of network IPs
alias ips="ifconfig -a | perl -nle'/(\d+\.\d+\.\d+\.\d+)/ && print $1'"
alias myip="dig +short myip.opendns.com @resolver1.opendns.com"
alias flush="dscacheutil -flushcache" # Flush DNS cache

alias gzip="gzip -9n" # set strongest compression level as ‘default’ for gzip
alias ping="ping -c 5" # ping 5 times ‘by default’
alias ql="qlmanage -p 2>/dev/null" # preview a file using QuickLook

# Upload image to Imgur and return its URL. Get API key at http://imgur.com/register/api_anon
imgur() { curl -F "image=@$1" -F "key=ANONYMOUS_IMGUR_API_KEY" https://api.imgur.com/2/upload | egrep -o "<original>.+?</original>" | egrep -o "http://imgur\.com/[^<]+" | sed "s/imgur.com/i.imgur.com/" | tee >(pbcopy); }

All of these are in my ~/.bash_profile so I can use them in every Terminal window.

P.S.

alias chpwn="chown"

For more, see my dotfiles repository on GitHub, and/or view my .osx file for OS X-specific preferences and settings.

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up vote 16 down vote

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.

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up vote 15 down vote

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.

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4  
I've used 'mate .' more times than I care to count. – Jarrod Oct 25 '09 at 17:02
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up vote 15 down vote

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.

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up vote 15 down vote

Resample image so height and width aren't greater than specified size, e.g. 100x100:

sips -Z 100x100 image.jpg

sips supports other operations such as: flip, rotate, crop, image properties query, colour profile query and modification. Check man sips for usage.

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up vote 14 down vote

history shows a list of the recent commands you've run — something like 500 or 600 commands. I frequently use history | grep something to find a command i've used recently.

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10  
That's a bash builtin, not OS X specific. – Tadeusz A. Kadłubowski Oct 8 '09 at 6:00
6  
You can press Ctrl+R in bash to interactively search through your shell history. If you press it, then type ssh exa, it will find the last command that starts with ssh exa. You can press ctrl+r again to cycle further backwards, return to execute the current command, or press escape to further edit the command – dbr Oct 25 '09 at 18:18
2  
While we're at it, history -a; history -r copies history between terminal tabs. – porneL Jul 6 '10 at 13:21
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Once you've run history you can run any item from the resulting list by using the history item's number. e.g. !23 will run item 23 in the history list. – drylight Jul 10 '10 at 6:16
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up vote 14 down vote

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
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