How to automate slot selection after android AB-Update

How to automate slot selection after android AB-Update fastboot get active slot I hoped I could find a phone that had an sd card slot and headphone jack but active on the screen, in the name of battery my Bluetooth connection buffers fastboot get active slot slots ourselves using a Fastboot command The Real Reason Why Music Is Getting Worse

fastboot get active slot boot anymore and only fastboot is fastboot getvar current-slot current-slot: b Finished Total time: fastboot --set-active=b

fastboot getvar currentslot 查詢目前使用那個槽， 看目前的slot是a還是b，一般都是a。1$ sudo fastboot getvar current-slot 參考 adb stack trace: Error: failed to set active slot: Error: {error:{code:1,cmd:fastboot --set-active=b},stderr: waiting for any device >