(Q) Fastboot on mac? (D855 V30N)

[DMCrimson78]

Okay, so I have the latest Android Studio installed and ADB sees my phone just fine, I can pull from /system/, but not push into. (Not rooted, the device needs to be taken to service to replace the LCD) But when I try to use fastboot to mount system rw so I could push modified build.prop back, it just sits there "waiting for any device". Is this due to mac or V30N? Basically i'm trying to enable Multi Window for all apps.

 

[audit13]

It's my understanding that adb commands can only be issued to the phone with the phone booted into the rom or when in recovery.

Fastboot commands can only be issued with the phone in bootloader mode.