# Using SheepShaver

## Changing the display mode

SheepShaver can display the MacOS user interface in an X11 window or full-screen (much faster). You select the display mode as usual under MacOS in the "Monitors" control panel (under System 7.x, click on "Options"). The "75Hz" modes are full-screen modes, the "60Hz" modes are window modes (this doesn't mean that the video refresh rate is 75 or 60Hz in the respective modes; the rate displayed has no meaning; it's simply there to distinguish full screen modes from window modes).

## Full-screen mode

The full-screen mode uses the whole X11 screen for displaying the MacOS user interface. You can temporarily switch back to the X11 desktop by pressing Ctrl-Tab. The MacOS (and all MacOS applications) will now be suspended. You can resume SheepShaver by activating the "SheepShaver suspended" window and pressing the space key. Using full-screen mode requires a DGA capable X server.

## Networking

There are three approaches to networking with SheepShaver:

1. Direct access to an Ethernet card via the "sheep_net" driver. In this case, the "ethernet card description" must be the name of a real Ethernet card, e.g. "eth0". It also requires the "sheep_net" driver to be installed and accessible. This approach will allow you to run all networking protocols under MacOS (TCP/IP, AppleTalk, IPX etc.) but there is no connection between Linux networking and MacOS networking. MacOS will only be able to talk to other machines on the Ethernet, but not to other networks that your Linux box routes (e.g. a second Ethernet or a PPP connection to the Internet).
2. Putting SheepShaver on a virtual Ethernet via the "ethertap" device. In this case, the "ethernet card description" must be the name of an ethertap interface, e.g. "tap0". It also requires that you configure your kernel to enable routing and the ethertap device: under "Networking options", enable "Kernel/User netlink socket" and "Netlink device emulation", under "Network device support", activate "Ethertap network tap". You also have to modify `devices/net/ethertap.c` a bit before compiling the new kernel:
   - insert `#define CONFIG_ETHERTAP_MC 1` near the top (after the `#include` lines)
   - comment out the line `dev->flags|=IFF_NOARP;` in `ethertap_probe()`

   Next, see `/usr/src/linux/Documentation/networking/ethertap.txt` for information on how to set up `/dev/tap*` device nodes and activate the ethertap interface. Under MacOS, select an IP address that is on the virtual network and set the default gateway to the IP address of the ethertap interface. This approach will let you access all networks that your Linux box has access to (especially, if your Linux box has a dial-up Internet connection and is configured for IP masquerading, you can access the Internet from MacOS). The drawback is that you can only use network protocols that Linux can route, so you have to install and configure netatalk if you want to use AppleTalk. Here is an example `/etc/atalk/atalkd.conf` for a LAN:

       eth0 -seed -phase 2 -net 1 -addr 1.47 -zone "Ethernet"
       tap0 -seed -phase 2 -net 2 -addr 2.47 -zone "Sheepnet"

   (the "47" is an arbitrary node number). This will set up a zone "Ethernet" (net 1) for the Ethernet and a zone "Sheepnet" (net 2) for the internal network connection of the ethertap interface. MacOS should automatically recognize the nets and zones upon startup. If you are in an existing AppleTalk network, you should contact your network administrator about the nets and zones you can use (instead of the ones given in the example above).
3. Networking protocols for serial connections (PPP and SLIP, for example) can be used provided that you have the appropriate MacOS system components installed (e.g. Open Transport/PPP).

## Using floppy disks

Floppy disks are not automatically detected when they are inserted. They have to be mounted explicitly: after inserting a floppy disk, press Ctrl-F1.

## Accessing Linux files

SheepShaver will display a "Linux" disk icon on the Mac desktop that allows you to access any Linux files which are in the directory specified as "Linux Root" in the "Volumes" pane of the SheepShaver settings. You can open and save files on the "Linux" disk from Mac applications, copy, move or rename files from the Finder etc. SheepShaver translates some file name extensions to MacOS types and vice versa, so e.g. *.jpg and *.pdf files will show the correct icons in the Finder. MacOS resources and Finder attributes are stored in hidden `.rsrc` and `.finf` directories.

## Copying text via the clipboard

SheepShaver tries to keep the Linux and MacOS clipboards synchronized. That means, when you copy a piece of text under Linux, you can paste it into a MacOS application and vice versa.