Prevent… -i idle system sleepThe usual choice: downloads, builds, scripts. -d display sleepKeep the screen on — presentations, dashboards. -m disk idle sleepRarely needed on SSD Macs. -s system sleep on AC powerOnly works while plugged in. -u declare the user activeWakes the display; lasts 5 s unless you set a time limit.

Time limit (minutes, optional)

Wait for process ID (optional)

…or run a command while awake (optional)

caffeinate -i

Lid closed? caffeinate can't. These flags block idle sleep. Closing a MacBook's lid without an external display sleeps the Mac anyway — that's a separate sleep path that power assertions don't cover. The only built-in override is the pmset switch below, and it doesn't turn itself off. Why, in detail →

pmset commands for the lid-closed case

Copy these as they are. They need an administrator password.

# disable all sleep, lid closed included (persistent!)
sudo pmset -a disablesleep 1

# check: 1 = sleep disabled, 0 = normal
pmset -g | grep SleepDisabled

# restore normal sleep — always run this afterwards
sudo pmset -a disablesleep 0

# what is keeping my Mac awake right now?
pmset -g assertions

If you'd rather not remember the last command, that's what Lidwork is for: it flips the switch from the menu bar and turns it back off on its own — when you toggle it, when the app crashes, and at your battery limit.

How to use the command

Open Terminal (Spotlight → “Terminal”).
Paste the command and press Return.
Leave the window open. Press Control-C to stop, or let the time limit / command end.