Xi386(1) X Version 11(Release 5) Xi386(1)
NAME
Xi386 - X Window System 16 color VGA server
SYNOPSIS
Xi386 [:displaynumber] [-option ...] [ttyname]
DESCRIPTION
Xi386 is the 16 color VGA server for the X Window System.
STARTING THE SERVER
The server is usually started from the X Display Manager program xdm.
This utility is run from the system boot files and takes care of keeping
the server running, prompting for usernames and passwords, and starting
up the user sessions. It is easily configured for sites that wish to
provide nice, consistent interfaces for novice users (loading convenient
sets of resources, starting up a window manager, clock, and nice
selection of terminal emulator windows).
Since xdm now handles automatic starting of the server in a portable way,
the -L option to xterm is now considered obsolete. Support for starting
a login window from 4.3bsd-derived /etc/ttys files is no longer included.
Installations that run more than one window system will still need to use
the xinit utility. However, xinit is to be considered a tool for
building startup scripts and is not intended for use by end users. Site
administrators are strongly urged to build nicer interfaces for novice
users.
When the sample server starts up, it takes over the display. If you are
running on a workstation whose console is the display, you cannot log
into the console while the server is running unless you switch virtual
terminals.
OPTIONS
The following options can be given on the command line to the AT&T X
server.
-auth authorization-file
Specifies a file which contains a collection of authorization
records used to authenticate access.
bc disables certain kinds of error checking, for bug compatibility
with previous releases (e.g., to work around bugs in R2 and R3
xterms and toolkits). Deprecated.
-bs disables backing store support on all screens.
10/89 Page 1
Xi386(1) X Version 11(Release 5) Xi386(1)
-cc class
sets the visual class for the root window of color screens. The
class numbers are as specified in the X protocol. Not obeyed by
all servers.
-co filename
sets name of RGB color database.
-dpi resolution
sets the resolution of the screen, in dots per inch. To be used
when the server cannot determine the screen size from the
hardware.
-fc cursorFont
sets default cursor font.
-fn font
sets the default font.
-fp fontPath
sets the search path for fonts. This path is a comma separated
list of directories which the sample server searches for font
databases. It also allows specification of one or more X11R5
font servers.
-help prints a usage message.
-I causes all remaining command line arguments to be ignored.
-logo turns on the X Window System logo display in the screen-saver.
This option requires that -v also be used since video blanking is
the default. There is currently no way to change this from a
client.
nologo turns off the X Window System logo display in the screen-saver.
There is currently no way to change this from a client.
-p seconds
sets screen-saver pattern cycle time in seconds.
-s seconds
sets screen-saver timeout time in seconds.
-su disables save under support on all screens.
-t number
sets pointer acceleration threshold in pixels (i.e. after how
many pixels pointer acceleration should take effect). <no action>
-to seconds
sets default connection timeout in seconds.
Page 2 10/89
Xi386(1) X Version 11(Release 5) Xi386(1)
ttyxx ignored, for servers started the ancient way (from init).
v sets video-on screen-saver preference.
-v sets video-off screen-saver preference.
-wm forces the default backing-store of all windows to be WhenMapped;
a cheap trick way of getting backing-store to apply to all
windows.
Many servers also have device-specific command line options. See the
manual pages for the individual servers for more details. The following
additional command line options are used by the AT&T X server:
-xnetaccess on|off
turns network access checking on or off.
-planes #
Device-dependent. Currently use 1 for setting monchrome, or 4, if
supported, for setting full color.
-lines #
screen height (pixels) desired. Give the height desired and the
appropriate matching width will be implied from the height. The
device dependent values are 640x350, 640x400, 640x480 (standard
VGA mode), 800x600, and 1024x768. 1024x768 is only used on
SVR4.0 systems.
-altstatic
use 'alternate' static colormap for VDC750 with CGA-style TTL
monitor.
-vgastatic
use static colormap which makes better use of VGA palette;
default map is compatible with EGA.
-kdmodenum #
specify a decimal number to be passed to the KD driver as the
graphics mode to switch to. For use when selecting VGA on
nonstandard OS versions based on SVR3.2. Avoid using this if you
are unsure what it means.
-vdctype <cntrlr>
override driver display-controller-type.
SECURITY
The sample server implements a simplistic authorization protocol, MIT-
MAGIC-COOKIE-1 which uses data private to authorized clients and the
server. This is a rather trivial scheme; if the client passes
authorization data which is the same as the server has, it is allowed
access. This scheme is worse than the host-based access control
10/89 Page 3
Xi386(1) X Version 11(Release 5) Xi386(1)
mechanisms in environments with unsecure networks as it allows any host
to connect, given that it has discovered the private key. But in many
environments, this level of security is better than the host-based scheme
as it allows access control per-user instead of per-host.
In addition, the server provides support for a DES-based authorization
scheme, XDM-AUTHORIZATION-1, which is more secure (given a secure key
distribution mechanism), but as DES is not generally distributable, the
implementation is missing routines to encrypt and decrypt the
authorization data. This authorization scheme can be used in conjunction
with XDMCP's authentication scheme, XDM-AUTHENTICATION-1 or in isolation.
The authorization data is passed to the server in a private file named
with the -auth command line option. Each time the server is about to
accept the first connection after a reset (or when the server is
starting), it reads this file. If this file contains any authorization
records, the local host is not automatically allowed access to the
server, and only clients which send one of the authorization records
contained in the file in the connection setup information will be allowed
access. See the Xau manual page for a description of the binary format
of this file. Maintenance of this file, and distribution of its contents
to remote sites for use there is left as an exercise for the reader.
The sample server also uses a host-based access control list for deciding
whether or not to accept connections from clients on a particular
machine. This list initially consists of the host on which the server is
running as well as any machines listed in the file /etc/Xn.hosts, where n
is the display number of the server. Each line of the file should
contain a hostname (e.g. expo.lcs.mit.edu) There should be no leading or
trailing spaces on any lines. For example:
joesworkstation
corporate.company.com
Users can add or remove hosts from this list and enable or disable access
control using the xhost command from the same machine as the server. For
example:
% xhost +janesworkstation
janesworkstation being added to access control list
% xhost -star
% xhost +
all hosts being allowed (access control disabled)
% xhost -
all hosts being restricted (access control enabled)
% xhost
access control enabled (only the following hosts are allowed)
joesworkstation
janesworkstation
corporate.company.com
Page 4 10/89
Xi386(1) X Version 11(Release 5) Xi386(1)
Unlike some window systems, X does not have any notion of window
operation permissions or place any restrictions on what a client can do;
if a program can connect to a display, it has full run of the screen.
Sites that have better authentication and authorization systems might
wish to make use of the hooks in the libraries and the server to provide
additional security models.
FONTS
Fonts are usually stored as individual files in directories. The list of
directories in which the server looks when trying to open a font is
controlled by the font path. Although most sites will choose to have the
server start up with the appropriate font path (using the -fp option
mentioned above), it can be overridden using the xset program.
The default font path for the sample server contains three directories:
/usr/lib/X11/fonts/misc (on SVR4.0)
or /usr/X/lib/fonts/misc (on SVR3.2)
This directory contains several miscellaneous fonts that are useful on
all systems. It contains a very small family of fixed-width fonts (6x10,
6x12, 6x13, 8x13, 8x13bold, and 9x15) and the cursor font. It also has
font name aliases for the commonly used fonts fixed and variable.
/usr/lib/X11/fonts/75dpi (on SVR4.0)
or /usr/X/lib/fonts/75dpi (on SVR3.2)
This directory contains fonts contributed by Adobe Systems, Inc. and
Digital Equipment Corporation and by Bitstream, Inc. for 75 dots per
inch displays. An integrated selection of sizes, styles, and weights are
provided for each family.
/usr/lib/X11/fonts/100dpi (on SVR4.0)
or /usr/X/lib/fonts/100dpi (on SVR3.2)
This directory contains versions of the fonts in the 75dpi directory for
100 dots per inch displays.
An additional directory /usr/lib/X11/fonts/Xol for SVR4.0 or
/usr/X/lib/fonts/Xol for SVR3.2, contains the OPEN LOOK fonts. This
directory is part of the server's default font path.
Font databases are created by running the mkfontdir program in the
directory containing the compiled versions of the fonts (the .snf files).
Whenever fonts are added to a directory, mkfontdir should be rerun so
that the server can find the new fonts. If mkfontdir is not run, the
server will not be able to find any fonts in the directory.
DIAGNOSTICS
Too numerous to list them all. If run from init(8), errors are logged in
the file /usr/adm/X*msgs,
10/89 Page 5
Xi386(1) X Version 11(Release 5) Xi386(1)
FILES
/etc/X*.hosts Initial access control list
/usr/lib/X11/fonts/misc, /usr/lib/X11/fonts/75dpi, /usr/lib/X11/fonts/100dpi
Font directories for SVR4.0
/usr/X/lib/fonts/misc,/usr/X/lib/fonts/75dpi/,/usr/X/lib/fonts/100dpi
Font directories on SVR3.2
/usr/lib/X11/rgb.<display_type>.txt
Color database on SVR4.0
/usr/X/lib/rgb.<display_type>.txt
Color database on SVR3.2
/usr/adm/X*msgs Error log file on SVR4.0
/usr/X/adm/X*msgs Error log file on SVR3.2
SEE ALSO
X(1), xdm(1), mkfontdir(1), xinit(1), xterm(1), twm(1), xhost(1),
xset(1), xsetroot(1), X Window System Protocol, Definition of the Porting
Layer for the X v11 Sample Server, and Strategies for Porting the X v11
Sample Server
BUGS
The option syntax is inconsistent with itself and xset(1).
The color database is missing a large number of colors. However, there
doesn't seem to be a better one available that can generate RGB values
tailorable to particular displays.
CAVEAT
The X server must be killed with a -2 and NOT a -9; this allows the
server environment to reset itself to its previous state. The X server
resets itself to default settings when no clients are active.
COPYRIGHT
Copyright 1984, 1985, 1986, 1987, 1988, 1989, Massachusetts Institute of
Technology.
Page 6 10/89