Check the battery level of connected bluetooth from command line in MacOS

such as Mouse and Keyboard

ioreg

ioreg -r -l -n AppleHSBluetoothDeviceto show all show I/O Kit registry.

There are lots of infonations. We can use egrep to get what we would

egrep

ioreg -r -l -n AppleHSBluetoothDevice | egrep ‘“BatteryPercent” = |^ \| “Bluetooth Product Name” = ‘

filter the keywords BatteryPercent and Bluetooth Product Name

Result:

amazing. next, we can format the output which look more readable.

sed

using sed to replace unuseful info

sed ‘s/”Bluetooth Product Name” = “Magic Mouse 2”/Mouse:/’
sed ‘s/”Bluetooth Product Name” = “Magic Keyboard with Touch ID”/ \| Keyboard:/’

and

sed ‘s/”BatteryPercent” = //’

command:

ioreg -r -l -n AppleHSBluetoothDevice | egrep '"BatteryPercent" = |^  \|   "Bluetooth Product Name" = '| sed 's/"Bluetooth Product Name" = "Magic Mouse 2"/Mouse:/' | sed 's/"Bluetooth Product Name" = "Magic Keyboard with Touch ID"/  \|  Keyboard:/'| sed 's/"BatteryPercent" = //'

Result:

Remove the unnecessary char and new line

remove the | char by sed 's/\|//g'

remove the new line and white space by using string//[$'\t\r\n\ ']

command:

BATTLVL=$(ioreg -r -l -n AppleHSBluetoothDevice | egrep '"BatteryPercent" = |^  \|   "Bluetooth Product Name" = '| sed 's/"Bluetooth Product Name" = "Magic Mouse 2"/Mouse:/' | sed 's/"Bluetooth Product Name" = "Magic Keyboard with Touch ID"/  \|  Keyboard:/'| sed 's/"BatteryPercent" = //' | sed "s/\|//g")
BATTRPT=${BATTLVL//[$'\t\r\n\ ']}
echo $BATTRPT

Result:

At last

let us make it formative by add the % to the number tail

sed -r 's/[0-9]+/\ &\%\n/g'

BATTLVL=$(ioreg -r -l -n AppleHSBluetoothDevice | egrep '"BatteryPercent" = |^  \|   "Bluetooth Product Name" = '| sed 's/"Bluetooth Product Name" = "Magic Mouse 2"/Mouse:/' | sed 's/"Bluetooth Product Name" = "Magic Keyboard with Touch ID"/  \|  Keyboard:/'| sed 's/"BatteryPercent" = //' | sed "s/\|//g")
BATTRPT=${BATTLVL//[$'\t\r\n\ ']}
# NOTE \d is not supported
echo $BATTRPT | sed -r 's/[0-9]+/\ &\%\n/g'

Result: