See also command lines it is tedious to remember for general Linux/unix/macOS/BSD commands.
⚠️ Most of these commands are supposed to be run sudo root, and each may irremediably fuck up your computer, your life, and everything you have ever loved. Then it might challenge you to a break dance battle, I dunno. It won’t be my fault.
So many of these were filesystem-specific hacks that I broke out those into an article on filesystem-specific hacks. And others were about easing the pains of using macOS in the low-bandwidth majority world or macOS server.
The remaining tips are arranged so that the further you get down the list the longer it is since I have needed to know it; the later ones probably don’t work on modern macOS.
Mathias Bynens and his incredible atomic dotfiles.
macOS Security and Privacy Guide.
As seen in typography. tl;dr
Cmd Ctrl Space.
"/System/Library/Automator/Combine PDF Pages.action/Contents/Resources/join.py" \ -o PATH/TO/YOUR/MERGED/FILE.pdf \ /PATH/TO/ORIGINAL/1.pdf \ /PATH/TO/ANOTHER/2.pdf \ /PATH/TO/A/WHOLE/DIR/*.pdf
If you are, e.g. concatenating chapters of a PDF book you downloaded from e.g. Springer, then you might have the creation dates in the correct order even if they are lexicographically correct. In that case you want (fish shell style)
pushd PATH/TO/PDFS "/System/Library/Automator/Combine PDF Pages.action/Contents/Resources/join.py" \ -o PATH/TO/YOUR/MERGED/FILE.pdf \ (ls -rUt)
There is some kind of problem with spaces in pathnames if you do it from a different folder.
Renew DHCP lease
My awful router gets cross if I leave the house and when I come back I try to use the same DHCP lease. But it’s a one-liner to fix.
Which file is crashing/hanging
Perpetual monitoring natively:
or the classic unix way:
See here for some tips on debugging runaway/hung/exploded processes in more ways. “See what syscalls does the process actually try to do and if there are any failed ones (status is not 0)” :
lsd runaway CPU
Some indexing jobs can cause it to choke, e.g. application bundles. Also, a corrupted database, which may be fixed thusly:
distnoted runaway CPU
This is some kind of notifications daemon. I have no idea why it is out of control. It seems to be related to other processes such as certain version of flux or bartender. but the problem only seems to occur when my backup drive is plugged in. Hmmph. File a ticket?
Michael Rourke suggests doing this every minute:
But note this will break backup, so maybe just don’t.
Mission control provides some window-arrangement tricks, mostly side-by-side tiling of selected windows, which they term Split View.
Mission Control Keyboard shortcuts of note:
^ ↑. The Split View itself has no shortcuts AFAICT.
Or you can commit your time to learning a workflow based on someone’s passion-project window system, which might or might not be sustainable.
Tyler Hoffman reviews two contenders, Amethyst and chunkwm.
Tiling window manager for macOS along the lines of xmonad.
Including various xmonad keyboard shortcuts, which is quicker if you like that thing.
chunkwm is a tiling window manager for macOS that uses a plugin architecture, successor to kwm. It represents windows as the leaves of a binary tree, and supports binary space partitioned, monocle and floating desktops.…
chunkwm runs a local daemon to receive messages on a dedicated socket (port 3920).…
A third party program (e.g:
skhd) is needed to map keyboard events to chunkwm actions.
But wait! There’s more!
Spectacle a macOS app that adds additional strategic window smushing options
Move to the left half — ⌥⌘←
Move to the right half — ⌥⌘→
Move to the top half — ⌥⌘↑
Move to the bottom half — ⌥⌘↓
Move to the upper left — ⌃⌘←
Move to the lower left — ⌃⇧⌘←
Move to the upper right — ⌃⌘→
Move to the lower right — ⌃⇧⌘→
Windows may also be resized between thirds using any of the shortcuts above. For example, to have a window resized between 1/3 and 2/3 of the left region of the screen simply activate the left half ⌥⌘← keyboard shortcut more than once.
Hammerspoon is fancy - it’s a window scripting interface sporting a whole Lua interpreter. Open source. It’s clearly much more than a window manager, and can do stuff like inspect USB events, click on menus, type for you etc.
⚠️ Yak shaving risk. ⚠️ Security risk. Proceed with caution.
Usage looks like this:
This reminds me… Hammertalk and Phoenix are contenders in another category:
However, people seemed to have converged on the UIKit accessibility API as a reasonable interface to script.
On this front, try Hammerspoon/Phoenix. pyatomac does the same for python but seems designed for UI testers not for UI users. You can do it with Applescript of course, if your heart overunneth with bituminous hate.
FFS iTunes never finishes syncing my phone it just stays stuck on “importing photos”
Because you don’t use iCloud, right? For one thing, why would you voluntarily put your private photos in the hands of some notoriously secretive third party? For another, even if you wanted to, if you live in a bandwidth-poor country, iCloud sync is not just bad, it’s comedically bad. Atrociously, OS-floggingly slow and glitchy. “iClod”, let us call it. So you sync using a cable and iTunes, of course.
Except that, every couple of days, that breaks. Heres how to fix it. (Note that this question refers to “iPhoto”, but the same bug has been faithfully carried over and reproduced in Aperture and Photos by diligent Apple devs, and the same fix works.)
Note that this will reset iTunes to not sync your images, so you might need to reconstruct your settings.
Do that, try again.
Creating GUIs for shell scripts
Automatically anonymized system stats
Change default shell
If you are reading this you are enough of a geek to need xcode
plist files are opaque binary messes
This is how to convert them to text. If you regard XML as text.
Now my machine won’t boot properly heeeeeelp
I wouldn’t panic yet, probably the bootloadey whodangle thingy is broken again.
(Also applies if your CPU fan is going all the time, your machine is pausing lots, you are having trouble getting laid, or a global geopolitical malaise is leading to the ineluctable slide of civilisation into ecosocial catastrophe.)
Do these things:
- Reset the SMC: Switch the computer off, then, while off, on the built-in keyboard, press the (left side) Shift-Control-Option keys and the power button at the same time.
- Reset the PRAM: Switch the computer off, then, while booting, press and hold the Option-Command-P-R keys until the startup sound chimes again.
- Build a small pyramid over your laptop from bronze and crystals. Burn some incense and your Applecare guarantee in a brazier atop it. Surround it with small pictures of your departed ancestors. Make an offering of fruit and prayer.
Other boot key combos of note
- offer a boot menu
- boot up off CD/USB
- Recovery OS
- Safe mode
- verbose mode
- single user prompt
Networking from the command line
Turning it off and on again
See also network hacks.
Turn on wifi on your macbook from the Mac macOS terminal command line:
List available wifi networks from the Mac macOS terminal command line:
Join a wifi network from the Mac macOS terminal command line:
Find your network interface name:
DNS is choked up
Oh no! did you use your computer in some wacky workplace network that DNS blocks “frivolous” websites? You need to flush it.
DNS flush command keeps changing, eh?:
More generally, avoid the problem with upgraded DNS.
Stop stealing focus from me, slow app, I clicked on you like 30 seconds ago
CNET says: How to keep applications from stealing focus. But their first idea (edit application, break code signature) is not a viable idea in the modern world.
The command-line background-open still works, although if I wanted to launch apps this way I would be using Linux.
The Apple supported solution is for you to buy a faster computer.
Saving 300MB from skype on general principle
Update: the new version of Skype actually keeps this offal in the cache folder. (I imagine this is purely because of my passive-aggressive complaining. You’re welcome.) So now you don’t need to delete it. Unless you are deleting skype, which I did.
Updated update: Never install skype! If you must use it, use a web version.
Since Skype is spookware I keep on my hard disk out of necessity, I am always mildly offended that it takes up 300MB of hard disk space for cached emoji for every single Skype username. (update: last time I checked they had managed to get it down to 200mb; still too much.)
This is all to store videos of Fozzie Bear and Christmas ornaments. The biggest Emoji-jockey on earth will never use 90% of this shit, and even though it claims to be a “cache”, it’s not in a cache folder, so it clogs up your backups with Fozzie Bear pictures. Put this in a launch agent:
Don’t worry, Skype still works, and recreates the folder for you with the obsessiveness of a meth addict trying to polish your windshield; really you just need to remember that some Skype calls might be free in dollars, but they bill you 300mb of disk space/bandwidth for every call as well as the recordings of your cybersex, but you can get the 300MB disk space back afterwards, whereas the dick pics are lost to the US government forever. (It doesn’t seem to work if you trigger it from a folder action, so I set up a cron job to run that command every 10 minutes.)
Stop gamed and other processes leaking your data and wasting precious network sockets for no reason
binary bob says :
in reference to this.
macOS claims it forgot my email/contacts/calendar password again
Then an hour later it forgets again again?
Woe! I fixed this once then I forgot how I did it.
Linkdump while I sort it out again again again:
Continuous [sic] request for the CalDAV password? Here’s one solution:
- Go to the Apple menu and choose System Preferences
- Choose the ‘iCloud’ preference pane
- Sign in to iCloud at the OS X preference panel – note if you’re already signed in here but still seeing the pop-up message, you can sign out then sign back in to stop that password prompt from happening again
- Close System Preferences
Using Chromium (“open-source chrome”)
Harder than it should be; Google really wants you to use their furtively modified alternate branch, Google Chrome.
Anyway, here is a supplier of unsullied Chromium.
Preview.app is illegible, blurry, slow
Yeah, some versions were broken. The official solution is to Turn it off and on again.
I found the problem could be avoided by using Skim.app.
I can’t even remember why I needed to do this, or how I worked it out, but geez it saved my bacon from something or other.
My arbitrary server process is running out of file handles
Hmm, who knows how this works on the latest versions?
But the traditional advice is:
How do I stop my disk filling up with temporary backups?
WHAT CRAP IS THIS: OS X’s MOBILEBACKUPS:
This shouldn’t be necessary, but I noticed that my spotlight indexing was stuck on the mobilebackups folder for some reason. Why was it even?
Re-time stupid alarms
By default, if you use notifications from Apple Calendar, the notification for events is at 9am, right in the middle of the first meeting of the day. So you are half way through the report-back presentation about your recent conference visit, your laptop pops up RECTAL EXAMINATION TODAY.
You aren’t supposed to be able to change this because the thought of this cruelty is all that gets jaded Apple executives out of bed in the morning, but there is a hack they forgot to stop.