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Magic Mouse Low Battery Alert

samselfridge on September 14, 2021

One of the worst things about the Apple Magic mouse is the fact that the OS doesn't give you any kind of low battery alert until it hits 2% battery...
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sjimmie profile image
Simon •

I too was getting quite annoyed only getting a battery-low warning at 2%. This script is a great workaround.
The only thing I had to add was the path to ioreg as the cron job could not find it

PATH=/usr/sbin:$PATH

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David Tepper •

Where does this code go?

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Simon •

In the mouseCheck.sh, just before the 'BATT=..' command

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Sander •

Thank you for posting this! So annoying Apple hasn't built in their own warning. One typo though: Hit CMD + D to return to terminal prompt should be CTR + D (control).

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Richard Weinstock • • Edited

This script is absolutely beautiful, thank-you so much!

Here are some recommendations:

If you have multiple mice or keyboards, consider only the one having the lowest battery level:

BATT=ioreg -c AppleDeviceManagementHIDEventService -r -l | grep -i mouse -A 20 | grep BatteryPercent | cut -d= -f2 | cut -d' ' -f2 | sort -n | head -1

KEY_BATT=ioreg -c AppleDeviceManagementHIDEventService -r -l | grep -i "Magic Keyboard" -A 20 | grep BatteryPercent | cut -d= -f2 | cut -d' ' -f2 | sort -n | head -1

If you would like to play a sound (From /System/Library/Sounds) along with the notification:

osascript -e "display notification \"Mouse battery is at ${BATT}%.\" with title \"Mouse Battery Low\" sound name \"Bottle\""

osascript -e "display notification \"Keyboard battery is at ${KEY_BATT}%.\" with title \"Keyboard Battery Low\" sound name \"Bottle\""

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Matt •

You can also check if the mouse is charging with the following:

CHARGING=`ioreg -c AppleDeviceManagementHIDEventService -r -l | grep -i mouse -A 20 | grep Transport | cut -d= -f2 | cut -d' ' -f2 | cut -d'"' -f2`

if [ "$CHARGING" = "USB" ]; then
  exit 0
fi
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djtnut profile image
David Tepper •

When I save the crontab file, it's tacking on this weird extension at the end of the file. See screenshot attached.

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Simon •

That's normal. You are not editing the crontab file directly. Once you save this tmp file and it contains no errors, it will overwrite the actual cron file (in /var/at/tabs/)

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Andrew Shaw •

Using display alert instead of display notification may be more appropriate