There are four options. All these four options enable you to run qemu on pure text console.
1) qemu-system-x86_64 -display vnc=127.0.0.1:0
will start qemu in headless mode.
You can later view the output by using a VNC viewer.
2) qemu-system-x86_64 -display curses
will start qemu in curses mode. Only text output is visible.
3) If you completely don't want to ever see the display, then use -display none
.
With (1), (2), and (3) the guest OS can still run in graphical mode (qemu still emulates a graphic card), except that on the option (2) you can only see things when the guest OS is display text, and (3) you can't see that the guest OS is displaying at all.
4) If you don't want to have a graphics card at all, then use qemu-system-x86_64 -nographic
instead. This boots qemu with the emulated serial console connected, your guest OS should be better be prepared to live without a graphic card and talk over the serial console, otherwise, you will see absolutely nothing and the system may not even be able to boot.
All the options allow you to start qemu in linux virtual console. But beware, one is not like the other. Fatdog as a guess OS support (1), (2), and (3) but not (4). (Not that it cannot be modified; it can, easy actually, but it does not support serial console by default, because ... well, who uses serial console by default on a PC?)