Running XFree86

Information for Linux Users : Running XFree86
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## 4. Running XFree86

XFree86 requires about 4mb of virtual memory to run, although having 8mb of RAM is probably the minimum comfortable configuration. A 387 coprocessor is helpful for 386 machines, although greater gains in interactive performance are obtained with an increase in physical memory. Also, a faster graphics card, bus or RAM, will improve server performance.

After unpacking the tar files, you need to include `/usr/X11R6/lib` in `/etc/ld.so.conf` (where it should already be by default) or in your `LD_LIBRARY_PATH` environment variable. Also, the configuration file `/etc/XF86Config` or `/usr/X11R6/lib/X11/XF86Config` must be properly filled out based on the host setup. Ideally this is done using `XF86Setup` or (if for some reason this doesn't work) using `xf86config`. If you really insist in hand-creating your config file use `XF86Config.eg` as a starting point and `README.Config` as guideline. You may damage your hardware if you use a wrong `XF86Config` file, so read the docs, especially the man pages and the other `README` files in `/usr/X11R6/lib/X11/doc`.

XFree86 has the ability to perform VT switching to and from the X server. When first started, XFree86 will automatically locate the first available VT (one that hasn't been opened by any process), and run on that VT. If there isn't one available, XFree86 will terminate with an error message. The server can be run on a specific VT by using the ``vt<nn>'' option, where <nn> is the number of an available VT (starting from 1). If you don't have a free VT XFree86 cannot run. Normally you can simply disable one of the `getty` programs in `/etc/inittab`, but if this is not an option, you can increase the number of available VTs by increasing the value of `NR_CONSOLES` in `include/linux/tty.h` and recompiling the kernel.

Once running inside X, switching to another VT is accomplished by pressing Ctrl-Alt-<Fnn> where nn is the number of the VT to switch to. To return to the server, press the proper key-combination that moves you back to the VT that XFree86 is using: by default, this is Alt-<Fmm>, where mm is the number of the VT the server is running on (this number is printed when the server is started). Note that this is NOT the VT from which the server was started.

NOTE: you can redefine the text-mode keybindings with the ``loadkeys`' command found in the `kbd-0.81.tar.gz` archive (or a later version thereof). With this, you can (for example) make Ctrl-Alt-<Fmm> work from text mode the same way it works under the XFree86 server.

When the server is exited, it will return to the original VT it was started from, unless it dies unexpectedly, when the switch must be done manually. There still seem to be weird combinations of graphic cards and motherboards that have problems to restore the textfont when returning from XFree86 to the text mode. In these cases using the `runx` script from the svgalib distribution might help.

The XFree86 server now queries the kernel to obtain the key binding in effect at startup. These bindings are either the default map in place when the kernel was compiled, or reloaded using the ``loadkeys`' utility. Not all keys are bound: kernel-specific, multiple keysym, and dead keys are not handled by the server. All others are translated to their X equivalents. Note that the XFree86 server only allows for four modifier maps: unshifted, shifted, modeswitch unshifted and modeswitch shifted. Depending on what the modeswitch key is (it is configurable in your `XF86Config` and defaults to Alt), XFree86 will read those tables into its keymaps. This means if you use certain keys, like left-Control, for Linux modeswitch, that will not be mappable to X.

Information for Linux Users : Running XFree86
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