[Qemu-devel] Re: more about serial ports: do they even work?

[Stefano Stabellini]

Michael Tokarev wrote:

> Other than that, an.. excellent idea, I wanted to propose
> just that when I first saw all this stuff, but was somewhat
> afraid.  And I *think* there's at least *some* sense.  Qemu
> is a CPU emulator and may work on another arch where those
> bits are defined differently.  Maybe that was the reason for
> all this converting - to be safe than sorry, so to say.  No?
> 

Yes, this is exactly the reason why they were introduced in the first place.
Let's suppose that the guest defines those constants differently: we
need to parse them and covert them appropriately to the host format.
CHR_IOCTL_SERIAL_SET_TIOCM and CHR_TIOCM_DTR correspond to the guest
version of TIOCMSET and TIOCM_DTR and can be defined differently
depending on the particular guest arch.