If for any reason you need to restart your X display manager, this can be done using xsetup, whether or not you choose to switch from one display manager to another. Alternatively, the X display manager can be stopped, started, or restarted using the /sbin/init.d/xlogin command with stop, start, or restart specified as the parameter.

For further information on configuring CDE and dtlogin, refer to Common Desktop Environment: User's Guide.

The information in the rest of this chapter primarily applies if you choose to run xdm. While dtlogin is similar to xdm and uses the same methods and concepts, there are important differences in the details.

This section presents a summary of the X security environment. Refer to the X Window System Administrator's Guide for details about implementing X security mechanisms for your system.

There are two approaches to X Window System security: host-based security and user-based security. The next sections briefly discuss each type.

Another host-based security mechanism involves using the /etc/Xn.hosts file to list systems that can access the local server, specified by n. However, this method is not recommended because it is hard to maintain a truly limited list of hosts if more than one user has access to the workstation where the list resides and because the method allows access to the X server at any time, even when the xdm login window appears.

The xdm-config resources DisplayManager.DISPLAY.authorize and DisplayManager.DISPLAY.authName control whether xdm uses authorization for local displays. X terminals using XDMCP negotiate with xdm to determine which mechanism to use.

You can invoke the failsafe mode by pressing the F1 or F2 key after typing your password in the login box. Do not press the Return key.

If you are able to log in, but only a single terminal window appears, you are already in failsafe mode.

Once you are in failsafe mode, you can check the errors in the xdm-errors file; check for errors in the xsession script, Xsession file, Xserver-conf file, or xdm-config file; or delete files if the user disk is full.

/usr/shlib/X11

 ! Default configuration file for extensible X server

! no other sysyem files are needed
! no other core files are needed
!

! device <
! >

! You can set alternate library search paths here or supplement the
! default path.
! library_path < /newserver/fonts/lib/font:/usr/shlib >

! Add a few more extensions
extensions < 
        < extdpms       libextdpms.so           DPMSExtensionInit       DPMS >   
        < dbe   libdbe.so       DbeExtensionInit        DOUBLE-BUFFER >
        < extshape      libextshape.so  ShapeExtensionInit      SHAPE   > 
        < extMultibuf libextMultibuf.so MultibufferExtensionInit Multi-Buffering >
! The KME extension is obsolete functionality that supports lock down
! and latching modifiers.  It has been replaced by the XKB extension
! and is only provided here for interoperability with R5 servers.
        < extkme     libextkme.so    KMEInit Keyboard-Management-Extension >
        < extMITMi   libextMITMisc.  MITMiscExtensionInit MIT-SUNDRY-NONSTANDARD >
        < extScrnSvr libextScrnSvr.so ScreenSaverExtensionInit MIT-SCREEN-SAVER >
        < extSync       libextSync.so   SyncExtensionInit       SYNC >
        < extxtest      libextxtest.so  XTestExtensionInit      XTEST >
        < extbigreq     libextbigreq.so BigReqExtensionInit     BIG-REQUESTS >
        < extXCMisc     libextXCMisc.so XCMiscExtensionInit     XC-MISC >
        ! add the xtrap extension
        < extxtrap      libextxtrap.so  DEC_XTRAPInit   DEC-XTRAP >

        ! add the video extension along with device specific handlers
        ! for the TX device
        < xv    libxv.so        XvExtensionInit XVideo
                < _dec_xv_tx lib_dec_xv_tx.so XvropScreenInit PMAG-RO >
                < _dec_xv_tx lib_dec_xv_tx.so XvropScreenInit PMAG-JA >
        >

 
        ! add the X imaging extension
!not R6 < _dec_xie      lib_dec_xie.so  Xie3Init        Xie >
        < dixie         libdixie.so     XieInit         XIE
                < mixie libmixie.so >
        >
        < _adobe_dps lib_adobe_dps.so XDPSExtensionDeferredInit  Adobe-DPS-Extension >
        < _adobe_dps lib_adobe_dps.so XDPSExtensionDeferredInit  DPSExtension >
>

! Load Speedo and Type1 renderers and
! enable communication with a font server
font_renderers <
        < fr_fs         libfr_fs.so     fs_register_fpe_functions >
        < fr_Speedo     libfr_Speedo.so SpeedoRegisterFontFileFunctions >
        < fr_Type1      libfr_Type1.so  Type1RegisterFontFileFunctions >
>

! Enable X Input Devices
!input <
!       Dial and Button Box on port /dev/tty01
!       < _dec_xi_pcm   lib_dec_xi_pcm.so       XiPcmInit /dev/tty01 >
!
!       Serial Mouse.  Use the following format for the last parameter:
!
!       device:type:baud:emulate3:chordmid:samplerate:cleardtr:clearrts:core
!
!       where
!
!       device:         The port the device is connectd to.
!                       For example, /dev/tty00.  /dev/tty00 is the
!                       default.
!
!       type:           The mouse type.  It must be one of the following
!                       strings (case does not matter):  microsoft
!                       mousesystems mmseries logitech busmouse mouseman
!                       ps/2 mmhittab.  mousesystems is the default.

!       baud:           The baud rate of the mouse.  Mine is 1200, I think
!                       others will do 9600.  1200 is the default.
!
!       emulate3:       Either 0 or 1.  1 means emulate a 3 button mouse
!                       with a 2 button mouse.  This is not implemented yet,
!                       though 0 is the default.
!
!       chordmid:       Either 0 or 1.  Some 3 button mice treat MB2 kind of
!                       whacky.  A value of 1 supports those meesers.  0 is
!                       the default.
!
!       samplerate:     The sample rate of the mouse.  I don't have a mouse
!                       that supports this, so I don't know what it does.
!                       150 is the default.
!
!       cleardtr:       Either 0 or 1.  1 means clear the DTR signal for
!                       the port before using the mouse.  0 is the default.
!
!       clearrts:       Either 0 or 1.  1 means clear the RTS signal for
!                       the port before using the mouse.  0 is the default.
!
!       core:           Either 0 or 1.  1 means make this emulate the core
!                       device.  0 means make it a two relative motion
!                       valuator, n-button X Input Device.  0 isn't
!                       implemented yet.  1 is the default.
!
!        < _dec_xi_serial_mouse lib_dec_xi_serial_mouse.so XiSerialMouseInit /dev/tty00:
microsoft:1200:1 >
!>
! transport and auth_protocol library loading is not yet supported

! you specify command line arguments here
args <
        -pn
>!

The X server has been modified to query the kernel automatically for the language and keyboard of the console. Given this information, the X server will examine the contents of the /usr/lib/X11/xkb/keymaps.dir file to determine which default keymap to use. The X server will then compile the keymap, place the compiled version in the directory /usr/lib/X11/xkb/compiled, and load it. This feature has been enabled by default. To disable it, add the -noloadxkb switch to the command line. If you wish to disable the XKB extension altogether, add the -kb switch to the command line. See the Xdec(1X) reference page or run Xdec with the -? option for more information.

In addition, the X Window System environment on Digital UNIX supports the following monitors:

     VRT16-HA/H4 16" 66/72HZ 1280x1024
     VRT19-HA/H4 19" 66/72HZ 1280x1024
     VRM17-HA/H4 17" 72HZ 1280x1024
     VR319-DA/D4 19" 72HZ 1280x1024
     VR320-Dx 19" 72HZ 1280x1024
     VR320-Cx 19" 66HZ 1280x1024
     VR160-Dx 16" 60HZ 1280x1024
     VR297-Dx 19" 60HZ 1024x864
     VR290-x 19" 60HZ 1024x864
     VR299-Dx 19" 60HZ 1024x864
     VRC16-Cx 17" 72HZ 1024x768

For X11 R6, the font server was renamed from fs to xfs. For compatibility, the symbolic link/usr/bin/X11/fs --> xfs is provided on Digital UNIX. Most X11 R5 and X11 R6 X servers can communicate with a font server. For example, Digital VXT V2.1 X terminals can communicate with the font server in the Digital UNIX operating system.

# font server configuration file
# $XConsortium: config.cpp,v 1.7 91/08/22 11:39:59 rws Exp $

clone-self = on
use-syslog = off
catalogue = /usr/lib/X11/fonts/decwin/100dpi/,
            /usr/lib/X11/fonts/decwin/75dpi/,
            /usr/lib/X11/fonts/misc/,
            /usr/lib/X11/fonts/75dpi/,
            /usr/lib/X11/fonts/100dpi/,
            /usr/lib/X11/fonts/Type1Adobe/,
            /usr/var/X11/fonts/user/misc/,
            /usr/var/X11/fonts/user/100dpi/,
            /usr/var/X11/fonts/user/75dpi/
error-file = /usr/var/X11/fs/fs-errors
# in decipoints
default-point-size = 120
default-resolutions = 75,75,100,100
renderers = libfr_Type1.so;
            Type1RegisterFontFileFunctions,libfr_Speedo.so;
            SpeedoRegisterFontFileFunctions

The following list explains the elements in the file:

• clone-self

  This line indicates whether the font server should try to clone itself or use delegates when it reaches the limit for number of clients. By default, the Digital UNIX font server clones itself when the limit is reached.

• use-syslog

  This line indicates whether or not syslog() is used for font server error logging. For Digital UNIX, the value is set to off, which means that, by default, errors are logged to the error-file specified in this configuration file.

• catalogue

  This line contains the list of font directories that are available by default from the Digital UNIX font server.

• error-file

  This line lists the pathname of the error log file. This file is used instead of syslog(). If you encounter problems after you have modified the configuration file, check the /usr/lib/X11/fs/fs-errors log file to debug your changes.

• default-point-size

  This line indicates the default point size for any font request that does not specify a point size. Note that the point size is specified in decipoints, so that a value of 120 indicates a point size of 12.

• default-resolutions

  This line lists the default resolutions supported by the Digital UNIX font server. The values are given in pairs of horizontal and vertical resolutions per inch.

• renderers

  This line defines the dynamically loaded renderer libraries for scalable fonts. These renderer libraries are the same font renderer libraries that can be loaded by the X server.

xset +fp tcp/hostname:7100

Replace the hostname variable with the name of the system where the font server is running.

You can create a script that automatically starts the font server when you boot your system in multiuser mode. Add a symbolic link to your script in /sbin/rc3.d. For example:

/sbin/rc3.d/S94fs -> ../init.d/fs