Keep Awake

One switch that keeps the screen on and the computer from sleeping, for a presentation, a long download or a build. No API keys, nothing leaves your computer.

What you see

• Tile: a coffee cup with "Off" while nothing is held, "On" in the accent colour while it is. A timed session shows the remaining time as hh:mm, ticking down without a single re-render.
• Flyout: the switch, five duration chips (30 min, 1 h, 2 h, 4 h, Until off), while on a hero with the end time and a live countdown, and a muted line naming the mechanism that holds the inhibit. The chips work while off (start for that long) and while on (change the duration).
• Hover: "Keep Awake · on for 42 more min" or "Keep Awake · off".
• Popup: "Keep Awake ended" when a timed session runs out.

The plugin always starts off. Nothing is remembered across a restart of smabar or the plugin, so a forgotten session can never keep a machine awake for days.

Requirements

• Linux: systemd-inhibit for sleep, plus one of these for screen idle: gnome-session-inhibit, the distro python3 with PyGObject (talks to org.freedesktop.ScreenSaver; GNOME, Cinnamon and MATE ship it), or xdg-screensaver on X11. Whatever exists is used, and the flyout shows which.
• macOS: caffeinate, part of the system.
• Windows: nothing extra; the plugin calls SetThreadExecutionState.

How it works

Platform	Mechanism
Linux	systemd-inhibit --what=idle:sleep --mode=block as a child process, plus the first screen-idle inhibitor that comes up: gnome-session-inhibit --inhibit idle, then inhibit_linux.py (a tiny helper that registers an org.freedesktop.ScreenSaver inhibit and holds the D-Bus connection open), then xdg-screensaver reset every 50 seconds.
macOS	caffeinate -dims -w <plugin pid>: display, idle, disk and system assertions.
Windows	SetThreadExecutionState(ES_CONTINUOUS | ES_SYSTEM_REQUIRED | ES_DISPLAY_REQUIRED) on a dedicated thread, cleared with ES_CONTINUOUS on stop.

Every inhibitor is tied to the plugin's own process: the Linux children wait for the plugin's pid (tail --pid), caffeinate -w waits for it, the Windows state dies with its thread. Switching off, a plugin reload or a graceful stop releases everything at once, and even a hard kill leaves nothing behind.

Settings

Setting	Default	Meaning
defaultMinutes	60	How long a session started with the switch or the on command lasts. 0 keeps the computer awake until you switch it off.

Agent commands

Command	Arguments	Result
on	minutes optional, 0 to 1440	Starts a session, or changes the duration of the running one.
off	none	Releases every inhibitor.
status	none	on, remainingMinutes, endsAt, mechanism, error.

Privacy

Everything stays local. The plugin starts a system tool or a helper process and writes no files at all.

Known limits

• On Cinnamon xdg-screensaver reset does nothing while the screensaver is inactive, which is why the D-Bus helper exists. Without PyGObject only sleep is inhibited there, not screen blanking; the flyout line shows systemd-inhibit alone in that case.
• Lid close, the power button and a sleep you trigger yourself are never blocked.
• Windows: SetThreadExecutionState keeps the display and the system awake but does not stop a classic screen saver.
• macOS: the system-sleep assertion (-s) applies on AC power only; on battery idle sleep is still prevented.
• The Windows and macOS backends follow the official documentation; they were built and verified on Linux (X11, Cinnamon).

Development

python3 test_backend.py checks the platform selection, the timer bookkeeping and the markup without a running bar and without starting any inhibitor.

#keep-awake #caffeine #sleep #screensaver #presentation #inhibit #power