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Caffeine-like utility to keep you MacBook awake with its lid closed

12 pointsposted 9 hours ago

27 Comments

tristanj

5 hours ago

Why download a third-party script when this feature is built into MacOS? Just run:

    sudo pmset -a disablesleep 1

to prevent macOS from sleeping. This works even when you close the lid and are on battery power. To re-enable normal sleep again, change the 1 to a 0.

clash

3 hours ago

1) Because you will eventually forget to reactivate it, which then leads to obvious problems.

2) Because you can for example be connected via ssh: You run the script and if your connection is disconnected, caffeinate+ shuts down the MacBook.

Edit: The API call that 'sudo pmset -a disablesleep 1' does is literally the first thing caffeine+ does. As soon as the lid closes the command is automatically reverted so you can't forget to do it yourself.

tristanj

a few seconds ago

Both of those are trivial to do in a few lines of shell. There's no need to download a custom tool for this. I asked Opus to draft one up and it's just five lines long.

    #!/bin/bash
    [ "$EUID" = 0 ] || exec sudo "$0" "$@"
    pmset -a disablesleep 1
    trap exit HUP INT TERM
    trap 'pmset -a disablesleep 0; ioreg -r -k AppleClamshellState | grep -q "State\" = Yes" && pmset sleepnow' EXIT
    "${@:-read}"

How to use it

    ./caf.sh              # stay awake until you press Enter
    ./caf.sh make build   # stay awake only while the command runs

Sleep is re-enabled when: the command finishes, the user presses Enter, on Ctrl-C, on SSH disconnect, or on kill (excluding SIGKILL). If the lid is closed when the command finishes, sleep is re-enabled and the Mac goes to sleep immediately.

nomel

6 hours ago

There are probably 20 of these at this point. I use amphetamine [1] (free on the app store). It has configurable timeouts with optional warnings/notifications, to reduce the ability for your MacBook to melt in your backpack. Can also have it disable when an app closes/download completes/battery percentage, and all sorts of triggers (like bluetooth presence, useful for backpack proximity).

[1] https://apps.apple.com/us/app/amphetamine/id937984704

clash

3 hours ago

Yeah, I obviously also did the research prior to implementing my solution.

I did not want GUI, just super simple caffeinate-like CLI. Also I wanted auto-shutdown afterwards.

smcleod

5 hours ago

[dead]

mathfailure

5 hours ago

Are those 20 free and open source as well? Name them then.

nomel

5 hours ago

My mistake. Well over 20.

https://www.google.com/search?q=site%3Agithub.com+keep+mac+o...

First one I used was around 9 years ago. Nearly melted my backpack with the hot Intel CPU!

If you don't want to install anything, you can disable sleep with the built in tools: sudo pmset -a disablesleep 1

clash

3 hours ago

Yeah, most of these repositories contain more files than caffeinate+ has lines of code.

The API call that 'sudo pmset -a disablesleep 1' does is literally the first thing caffeine+ does. But is only part of the full solution: As soon as the lid closes the command is automatically reverted so you can't forget to do it yourself. Also if you kill caffeinate+, the MacBook is put to sleep when the lid is still closed.

nomel

2 hours ago

Yes, most of the very many that you didn't know existed just a moment ago also handle that tricky case of restoring normal operation.

randomblock1

5 hours ago

I mean, yeah...

https://github.com/search?q=caffeinate+lid+close&type=reposi...

semiquaver

4 hours ago

What are you talking about? It’s a one line terminal invocation. These apps are utterly useless. Of course there’s a million open source ones.

clash

3 hours ago

Can your one line terminal invocation automatically put the MacBook to sleep when you are connected via ssh and the connection is lost?

nomel

2 hours ago

Technically one line ;)

    sudo bash -c 'trap "pmset -a disablesleep 0" EXIT; s=; while :; do if lsof -nP -iTCP:22 -sTCP:ESTABLISHED >/dev/null 2>&1 || pgrep -xq ssh;
  then n=1; else n=0; fi; [ "$n" != "$s" ] && pmset -a disablesleep $n && s=$n; sleep 10; done'

olyjohn

6 hours ago

This is neat. I ended up having to buy one of those dummy HDMI dongles to keep my MacBook awake so that I could remote into it. If it thinks there's an external monitor attached, it won't sleep. Or at least you can set it up that way.

dlivingston

2 hours ago

Just read through the source code. Very simple and the first non-AI coded project I've seen here in a while.

Nice work.

WarOnPrivacy

9 hours ago

Windows has been surprisingly good about this (lid closed, laptop awake). I have a number of always-closed laptops deployed for customers (+ mother in law). Some are desktops that can be easily moved; others are on-prem devices that are left alone to handle certain tasks.

This isn't my first reading about the struggles MacBook users have here. It is bizarre to me that Apple doesn't natively and reliably support closed+awake devices; it feels like they've dug in their heels and I can't imagine why.

el_benhameen

5 hours ago

Windows is so good at this that it refuses to let my work laptop sleep when I close it and put it in my backpack no matter how many settings I try tweaking.

cosmic_cheese

5 hours ago

For the desk setup scenario, it's less of a problem since they'll stay awake in clamshell if they've got a power source and are hooked up to an external monitor. I've used my personal MacBook in a hybrid home/work setup like this for years without issue. It's only if you want clamshell on battery and/or with no external monitor that tools like this become necessary.

user

5 hours ago

[deleted]

clash

9 hours ago

I wrote a small caffeine-like macOS command-line utility to keep your MacBook awake when you close the lid.

This can be handy when you have a long running task active but need to close your MacBook – for example to change trains, head home from a café or commute to the office.

WarOnPrivacy

9 hours ago

> I wrote a small caffeine-like macOS command-line utility to keep your MacBook awake when you close the lid.

Small purposeful utilities like this are Glob's own gift to us. Your counterpart in my Windows world might be the guy who wrote AlwaysActiveHours - a util that prevents update-related reboots.

1) It does not behave like caffeine where I can just kill the process and the behavior is reverted.

2) It does not put the MacBook to sleep automatically.

sys_64738

4 hours ago

brew install vorssaint

Thank me later.

clash

3 hours ago

Nope, not thanking you now or later.

1) It is an insane bloat if you just want that one feature. 2) There is no CLI, just GUI.