Quoting Volker Kuhlmann <[EMAIL PROTECTED]>:

<snip>
> 
> I have heard a few wow!s about the qemu in SuSE 10, which I will
> definitely try out as soon as I get the box media. Great for software
> testing I've heard.
> 
> As for the talk, I'm afraid I was a bit disappointed, because it was a
> bit inefficient and I came away without answers to some of the key

fair enough.
> questions pertinent to any such emulator: how (in principle) does qemu
> work,

It's essentially a JIT emulator for binaries.
http://fabrice.bellard.free.fr/qemu/qemu-doc.html
"QEMU is a FAST! processor emulator using dynamic translation to achieve good
emulation speed.

QEMU has two operating modes:

    * Full system emulation. In this mode, QEMU emulates a full system (for
example a PC), including a processor and various peripherals. It can be used to
launch different Operating Systems without rebooting the PC or to debug system 
code.
    * User mode emulation (Linux host only). In this mode, QEMU can launch Linux
processes compiled for one CPU on another CPU. It can be used to launch the Wine
Windows API emulator (http://www.winehq.org) or to ease cross-compilation and
cross-debugging. 

QEMU can run without an host kernel driver and yet gives acceptable 
performance. "
> how is the underlying host hardware handled,

Qemu's an app running inside the hostOS; it calls the host hardware via the
hostOS system calls just like any other app.
> how the guest
> hardware,

The guest hardware takes the system calls made to it, then hands them on down to
the hostOS system calls, which is where they get their work down.
> what's the compatibility with a range of common application
> software,

So far I've got several major-sized applications and application suites running
in MS Win9x under qemu on Linux.  I haven't had so much luck with MS WinNT 4.0,
but that's because I haven't installed any of the Service Packs.  The
applications include OO.org 1.1.4, Abiword, Sapphire (Accountancy package),
OpenWatcom 1.3, MinGW 3.4.2, Mozilla Firefox 1.0.4, Thunderbird, and some more
minor ones I can't recall offhand.

Mind you, for Win95 I needed to install MSVCRT.DLL before it would deign to
notice Mozilla Firefox. ;)
> peripheral support (USB, printer, typical doze-only
> fax/scanner/etc, sound!!!),
>From the documentation:
http://fabrice.bellard.free.fr/qemu/qemu-doc.html
"The QEMU System emulator simulates the following PC peripherals:

    * i440FX host PCI bridge and PIIX3 PCI to ISA bridge
    * Cirrus CLGD 5446 PCI VGA card or dummy VGA card with Bochs VESA extensions
(hardware level, including all non standard modes).
    * PS/2 mouse and keyboard
    * 2 PCI IDE interfaces with hard disk and CD-ROM support
    * Floppy disk
    * NE2000 PCI network adapters
    * Serial ports
    * Soundblaster 16 card 

QEMU uses the PC BIOS from the Bochs project and the Plex86/Bochs LGPL VGA 
BIOS. "

I don't know about USB at present.  At the moment I don't have any USB stuff,
and I haven't tried any sound-generating stuff either.

According to the documentation:
http://fabrice.bellard.free.fr/qemu/qemu-doc.html
"`-enable-audio'
    The SB16 emulation is disabled by default as it may give problems with
Windows. You can enable it manually with this option."

I'll try it when I get Doom installed. ;)

I was also thinking I could probably rustle up a USB driver by reading the Linux
and BSD USB modules, and comparing them with the specs and the (pre-existing)
qemu driver code.  (After all, how hard could it be?  Famous last words! ;)  But
don't count on it yet - I'm laziness personified. ;)

> file sharing between host and guest?
Documentation:
http://fabrice.bellard.free.fr/qemu/qemu-doc.html
"`-n script'
    Set TUN/TAP network init script [default=/etc/qemu-ifup]. This script is
launched to configure the host network interface (usually tun0) corresponding to
the virtual NE2000 card."
etc

"`-smb dir'
    When using the user mode network stack, activate a built-in SMB server so
that Windows OSes can access to the host files in `dir' transparently. In the
guest Windows OS, the line:

10.0.2.4 smbserver

    must be added in the file `C:\WINDOWS\LMHOSTS' (for windows 9x/Me) or
`C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS' (Windows NT/2000). Then `dir' can be
accessed in `\\smbserver\qemu'. Note that a SAMBA server must be installed on
the host OS in `/usr/sbin/smbd'. QEMU was tested succesfully with smbd version
2.2.7a from the Red Hat 9 and version 3.0.10-1.fc3 from Fedora Core 3."

I haven't been running qemu for long enough to have got a handle on the network
options.  my bad.  I was just glad enough to have it running satisfactorily
enough to try some Win32 (ReactOS and apps) projects I've got on the back 
burner.

And qemu has become the ReactOS emulator of choice, by all the comments on the
ReactOS lists.
> (Feel
> free to criticise my presentations... ;)
> 
> Volker
> 
> -- 
> Volker Kuhlmann                       is possibly list0570 with the domain in 
> header
> http://volker.dnsalias.net/           Please do not CC list postings to me.
>  



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