I am trying to install Redox OS with Virtual Box on my Ubuntu 18.04 machine. The "book" says this:
Trying Redox in a virtual machine
The ISO image is not the prefered way to run Redox in a virtual machine. Currently the ISO image loads the entire hard disk image (including unused space) into memory. In the future, the live disk should be improved so that doesn't happen.
Instead, you want to use the hard disk image, which you can find on the release pages as a .bin.gz file. Download and extract that file.
You can then run it in your prefered emulator; this command will run qemu with various features Redox can use enables:
qemu-system-x86_64 -serial mon:stdio -d cpu_reset -d guest_errors -smp 4 -m 1024 -s -machine q35 -device ich9-intel-hda -device hda-duplex -net nic,model=e1000 -net user -device nec-usb-xhci,id=xhci -device usb-tablet,bus=xhci.0 -enable-kvm -cpu host -drive file=redox_VERSION.bin,format=raw
Change redox_VERSION.bin to the .bin file you just downloaded.
Firstly, I couldn't find any .bin.gz file in the linked release pages. However, I was able to find one on their GitHub. Secondly, I don't understand where I'm supposed to run the mentioned command - in my ubuntu terminal? If I do, how will it open in Virtual Box? And what does "preferred emulator" mean? This is my first post in this stack exchange, so please tell me if any edits to the question are required. I also checked on the web - I couldn't find any answer to my questions.