[Qemu-discuss] How do I redirect console IO for script use?

[Joachim Durchholz]

Hi all,

new qemu user here.
I can't seem to find the options that do what I want, only options that 
*almost* do it.

I want to
- start a qemu VM from a shell script
- redirect just the physical console
  (not a pty or anything inside the VM)
- output should go to some file descriptor
  (stdout is fine, I know how to redirect descriptors)
- I would like to also have a window that shows the guest console
  so I can debug the script
- send keystrokes to the VM

The emulated machine is a standard 64-bit PC, with a monitor and 
keyboard (i.e. the console).

I already know that transforming the console to a character stream is 
somewhat icky, because the screen is just a two-dimensional character 
array, so qemu would have to observe the changes and reconstruct a 
series of control sequences that reproduce these changes.
Is that what -curses does? The description wasn't too clear for me.

I only need text mode, so graphics modes are a non-issue.

I tried reading the docs, but that didn't help for various reasons (lack 
of knowledge about which TLA is intended for what purpose - I can 
quickly rule out block device options, but is SPICE even a sensible 
thing to consider? ...  no idea, the docs don't tell me.)
I also tried stack overflow, but all the approaches that I found were 
talking about adding a kernel parameter, which I would like to avoid (I 
need to deal with FreeBSD, which I'm pretty unfamiliar with and I would 
be unable to deal with any variations of the device name, plus it's just 
another moving part that can fail, plus is't a difference between VM 
test runs and real hardware and I don't want to have to worry about that).

Any help appreciated!

Regards,
Jo