<othercredit role="translator"><firstname>John</firstname><surname>Knight</surname><affiliation><address><email>anarchist_tomato@herzeleid.net</email></address></affiliation><contrib>Conversion to British English</contrib></othercredit>
<para>&tdm; provides a graphical interface that allows you to log in to a system. It prompts for login (username) and password, authenticates the user and starts a <quote>session</quote>. &tdm; is superior to &xdm;, the X Display Manager, in a number of ways.</para>
<para>Each user will generally only use a single window manager or desktop environment, and does not change this choice very often, or is comfortable editing a single text file in order to change their choice.</para>
<para>This scenario will be sufficient for many environments where a single user or several users normally boot the computer and log into their preferred environment.</para>
<para>If one does not already exist, add a line to the <filename>~/.xinitrc</filename> to start your preferred window manager or desktop environment.</para>
<para>For &kde; you should enter:</para>
<screen><userinput>starttde</userinput></screen>
<para>For other window managers or desktop environments, you should look in their documentation for the correct command.</para>
<para>At this point, typing <userinput><command>startx</command></userinput> on the commandline should start X, with a &kde; session. The next task is to try &tdm;.</para>
<para>As <systemitem class="username">root</systemitem>, type <userinput><command>tdm</command></userinput> at the prompt.</para>
<para>You should see a login window, which is described more fully in<xref linkend="login"/>.</para>
<para>Typing your normal username and password in the fields provided, and leaving <option>default</option> selected as the session type should now open a &kde; session for your user.</para>
<para>If you have other users to configure, you should repeat the procedure above for each of them.</para>
<para>This is a quick guide to getting up and running only. You probably will want to customise &tdm; further, for example, to hide the names of the system accounts, to allow further sessions, and much more. Please read through the rest of this manual to find out how to do these things.</para>
<para>(Optionally) a graphical image of each user (for example, a digitised photograph). Clicking on an image is equivalent to typing the associated username into the <guilabel>Username:</guilabel> field. (This feature is an imitation of the login box on IRIX).</para> </listitem>
<para>A <guilabel>Menu</guilabel> drop-down box that allows &tdm; to be used to start sessions with various different window managers or desktop environments installed on the system.</para>
<para>(Optionally) a region to the right of the <guilabel>Username:</guilabel>, <guilabel>Password:</guilabel> and <guilabel>Session Type:</guilabel> fields which can be used to display either a static image or an analogue clock.</para>
<para>A <guibutton>Login</guibutton> button that validates the username/password combination and attempts to start a session of the selected type.</para>
<para>(On local displays) a <guimenuitem>Restart X Server</guimenuitem> item that terminates the currently running &X-Server;, starts a new one and displays the login dialogue again. You can use this if the display content seems to be broken somehow.</para>
<para>(On remote displays) A <guimenuitem>Close Connection</guimenuitem> item that closes the connection to the XDMCP server you are currently connected to. If you got to this server through a host chooser, this will bring you back to the chooser, otherwise it will only reset the &X-Server; and bring up the login dialogue again.</para>
<para>(Optionally on local displays) A <guimenuitem>Console Mode</guimenuitem> item that terminates the currently running &X-Server; and leaves you alone with a console login. &tdm; will resume the graphical login if nobody is logged in at the console for some time. To make this work, you need to use the local@<console> syntax in the <filename>Xservers</filename> file (see comments in that file).</para>
<listitem><para>Shut the system down and reboot. For systems that use <application>Lilo</application>, an optional drop-down box allows you to select a particular operating-system kernel to be used for the reboot.</para>
<para>Stop the &X-Server; and return the system to console mode. This is achieved by bringing the system down to run-level 3. Typically, the system manager might need to use this option before upgrading or re-configuring X11 software.</para>
<para>Pressing the <guibutton>OK</guibutton> button initiates the selected action; pressing the <guibutton>Cancel</guibutton> button returns to the main &tdm; dialogue box. </para>
<para>This chapter assumes that &tdm; is already up and running on your system, and that you simply want to change its behaviour in some way.</para>
<para>When &tdm; starts up, it reads its configuration from the folder <filename class="directory">$TDEDIR/share/config/tdm/</filename> (this may be <filename class="directory">/etc/kde3/tdm/</filename> or something else on your system).</para>
<para>The main configuration file is &tdmrc;; all other files are referenced from there and could be stored under any name anywhere on the system - but usually that would not make much sense for obvious reasons (one particular exception is referencing configuration files of an already installed &xdm; - however when a new &tdm; is installed, it will import settings from those files if it finds an already installed &xdm;).</para>
<para>Since &tdm; must run before any user is logged in, it is not associated with any particular user. Therefore, it is not possible to have user-specific configuration files; all users share the common &tdmrc;. It follows from this that the configuration of &tdm; can only be altered by those users that have write access to <filename>$<envar>TDEDIR</envar>/share/config/tdm/tdmrc</filename> (normally restricted to system administrators logged in as <systemitem class="username">root</systemitem>).</para>
<para>You can view the &tdmrc; file currently in use on your system, and you can configure &tdm; by editing this file. Alternatively, you can use the graphical configuration tool provided by the &kcontrolcenter; (under <menuchoice><guisubmenu>System Administration</guisubmenu><guimenuitem>Login Manager</guimenuitem></menuchoice>), which is described in <ulink url="help:/kcontrol/login-manager.html">the &kcontrol; help files</ulink>. </para>
<para>The remainder of this chapter describes configuration of &tdm; via the &kcontrol; module, and the <link linkend="tdm-files">next chapter</link> describes the options available in &tdmrc; itself. If you only need to configure for local users, the &kcontrol; module should be sufficient for your needs. If you need to configure remote logins, or have multiple &tdm; sessions running, you will need to read on.</para>
<othercredit role="translator"><firstname>John</firstname><surname>Knight</surname><affiliation><address><email>anarchist_tomato@herzeleid.net</email></address></affiliation><contrib>Conversion to British English</contrib></othercredit>
<para>Using this module, you can configure the &kde; graphical login manager, &tdm;. You can change how the login screen looks, who has access using the login manager and who can shutdown the computer.</para>
<note><para>All settings will be written to the configuration file &tdmrc;, which in it's original state has many comments to help you configure &tdm;. Using this &kcontrol; module will strip these comments from the file. All available options in &tdmrc; are covered in <xref linkend="tdm-files"/>.</para>
<para>The options listed in this chapter are cross referenced with their equivalents in &tdmrc;. All options available in the &kcontrol; module are also available directly in &tdmrc; but the reverse is not true.</para></note>
<para>In order to organise all of these options, this module is divided into several sections: <link linkend="tdmconfig-appearance"><guilabel>Appearance</guilabel></link>, <link linkend="tdmconfig-font"><guilabel>Font</guilabel></link>, <link linkend="tdmconfig-background"><guilabel>Background</guilabel></link>, <link linkend="tdmconfig-shutdown"><guilabel>Shutdown</guilabel></link>, <link linkend="tdmconfig-users"><guilabel>Users</guilabel></link> and <link linkend="tdmconfig-convenience"><guilabel>Convenience</guilabel></link>.</para>
<para>You can switch between the sections using the tabs at the top of the window.</para>
<note><para>If you are not currently logged in as a superuser, you will need to click the <guibutton>Administrator Mode</guibutton> Button. You will then be asked for a superuser password. Entering a correct password will allow you to modify the settings of this module.</para></note>
<para>From this page you can change the visual appearance of &tdm;, &kde;'s graphical login manager.</para>
<para>The <guilabel>Greeting:</guilabel> is the title of the login screen. Setting this is especially useful if you have many servers users may log in to. You may use various placeholders, which are described along with the corresponding key <link linkend="option-greetstring"><option>GreetString</option></link> in &tdmrc;. </para>
<para>You can then choose to show either the current system time, a logo or nothing special in the login box. Make your choice in the radio buttons labelled <guilabel>Logo area:</guilabel>. This corresponds to <link linkend="option-logoarea"><option>LogoArea</option></link> in &tdmrc;</para>
<para>If you chose <guilabel>Show logo</guilabel> you can now choose a logo:</para>
<para>If you do not specify a logo the default <filename>$<envar>TDEDIR</envar>/share/apps/tdm/pics/kdelogo.xpm</filename> will be displayed.</para>
<para>Normally the login box is centred on the screen. Use the <guilabel>Position:</guilabel> options if you want it to appear elsewhere on the screen. You can specify the relative position (percentage of the screen size) for the centre of the login window, relative to the top left of the display, in the fields labelled <guilabel>X:</guilabel> and <guilabel>Y:</guilabel> respectively. These correspond to the key <link linkend="option-greeterpos"><option>GreeterPos</option></link> in &tdmrc;.</para>
<para>While &kde;'s style depends on the settings of the user logged in, the style used by &tdm; can be configured using the <guilabel>GUI Style:</guilabel> and <guilabel>Colour Scheme:</guilabel> options. These correspond to the keys <link linkend="option-guistyle"><option>GUIStyle</option></link> and <link linkend="option-colorscheme"><option>ColorScheme</option></link> in &tdmrc; respectively.</para>
<para>Below that, you have a dropdown box to choose the language for your login box, corresponding to setting <option>Language</option> in &tdmrc;.</para>
<para>From this section of the module you can change the fonts used in the login window. Only fonts available to all users are available here, not fonts you have installed on a per user basis.</para>
<para>You can select three different font styles from the drop down box (<guilabel>General:</guilabel>, <guilabel>Failures:</guilabel>, <guilabel>Greeting</guilabel>). When you click on the <guibutton>Choose...</guibutton> button a dialogue appears from which you can select the new characteristics for the font style.</para>
<para>Here you can change the desktop background which will be displayed before a user logs in. You can have a single colour or an image as a background. If you have an image as the background and select centre, the selected background colour will be used around the image if it is not large enough to cover the entire desktop.</para>
<para>The background colours and effects are controlled by the options on the tab labelled <guilabel>Background</guilabel> and you select a background image and its placement from the options on the tab labelled <guilabel>Wallpaper</guilabel>.</para>
<para>The dropdown box above the colour buttons provides you with several different blend effects. Choose one from the list, and it will be previewed on the small monitor at the top of the window. Your choices are:</para>
<listitem><para>By choosing this mode, you select one colour (using the colour button labelled <guibutton>Colour 1</guibutton>), and the entire background is covered with this one colour.</para></listitem>
<listitem><para>By choosing this mode, you select two colours (using both colour buttons). </para> <para>You then select a pattern by clicking <guilabel>Setup</guilabel>. This opens a new dialogue window, which gives you the opportunity to select a pattern. Simply click once on the pattern of your choice, then click on <guilabel>OK</guilabel>, and &kde; will render the pattern you selected using the two colours you selected. For more on patterns, see the section <ulink url="help:/kcontrol/background/index.html#bkgnd-patterns">Background: Adding, Removing and Modifying Patterns</ulink>.</para></listitem>
<listitem><para>By selecting this option, you can have &kde; use an external program to determine the background. This can be any program of your choosing. For more information on this option, see the section entitled <ulink url="help:/kcontrol/background/index.html#bkgnd-programs">Background: Using an external program</ulink>.</para></listitem>
<listitem><para>By choosing this mode, you select two colours (using both colour buttons). &kde; will then start with the colour selected by <guilabel>Colour 1</guilabel> on the left edge of the screen, and slowly transform into the colour selected by <guilabel>Colour 2</guilabel> by the time it gets to the right edge of the screen.</para></listitem>
<listitem><para>By choosing this mode, you select two colours (using both colour buttons). &kde; will then start with the colour selected by <guilabel>Colour 1</guilabel> on the top edge of the screen, and slowly transform into the colour selected by <guilabel>Colour 2</guilabel> as it moves to the bottom of the screen.</para></listitem>
<listitem><para>By choosing this mode, you select two colours (using both colour buttons). &kde; will then start with the colour selected by <guilabel>Colour 1</guilabel> in each corner of the screen, and slowly transform into the colour selected by <guilabel>Colour 2</guilabel> as it moves to the centre of the screen.</para></listitem>
<listitem><para>By choosing this mode, you select two colours (using both colour buttons). &kde; will then start with the colour selected by <guilabel>Colour 1</guilabel> in each corner of the screen, and slowly transform into the colour selected by <guilabel>Colour 2</guilabel> as it moves to the centre of the screen. The <quote>shape</quote> of this gradient is different then the pyramid gradient.</para></listitem>
<listitem><para>By choosing this mode, you select two colours (using both colour buttons). &kde; will then start with the colour selected by <guilabel>Colour 2</guilabel> in the centre of the screen, and slowly transform into the colour selected by <guilabel>Colour 1</guilabel> as it moves to the edges, in an elliptical pattern.</para></listitem>
<para>The setup button is only needed for if you select <guilabel>Background program</guilabel> or <guilabel>Patterns</guilabel>. In these instances, another window will appear to configure the specifics.</para>
<para><emphasis>Wallpaper</emphasis></para>
<para>To select a new background image first, click on the <guilabel>Wallpapers</guilabel> tab, then you can either select an image from the drop-down list labelled <guilabel>Wallpaper</guilabel> or select <guibutton>Browse...</guibutton> and select an image file from a file selector.</para>
<para>The image can be displayed in six different ways:</para>
<listitem><para>The image will be duplicated until it fills the entire desktop. The first image will be placed in the upper left corner of the screen, and duplicated downward and to the right.</para> </listitem>
<listitem><para>The image will be duplicated until it fills the entire desktop. The first image will be placed in the centre of the screen, and duplicated upwards, downwards to the right, and to the left.</para> </listitem>
<listitem><para>The image will be placed in the centre of the screen. It will be scaled to fit the desktop, but it will not change the aspect ratio of the original image. This will provide you with an image that is not distorted. </para> </listitem>
<listitem><para><guilabel>Only Root</guilabel>: &tdm; requires that the <systemitem>root</systemitem> password be entered before shutting down the computer.</para></listitem>
<para>You can independently configure who is allowed to issue a shutdown command for the <guilabel>Local:</guilabel> and <guilabel>Remote:</guilabel> users.</para>
<para><emphasis>Commands</emphasis></para> <para>Use these text fields to define the exact shutdown command.</para> <para>The <guilabel>Halt:</guilabel> command defaults to <command>/sbin/halt</command>. The restart command defaults to <command>/sbin/reboot</command>.</para>
<para>When <guilabel>Show boot options</guilabel> is enabled, &tdm; will on reboot offer you options for the lilo boot manager. For this feature to work, you will need to supply the correct paths to your <command>lilo</command> command and to lilo's map file.</para>
<para>Define which session types should be accessible from the login window.</para>
<para>For more information on this subject, look at <filename class="directory">/etc/X11/xdm/Xsession</filename> to find your <application>xdm</application> setup files. Also review the <ulink url="man:xdm">xdm man pages</ulink>, especially under the SESSION PROGRAM section.</para>
<para>To add a session, type its name in the blank entitled <guilabel>New types</guilabel>, and click <guibutton>Add new</guibutton>. </para>
<para>To remove a session, select the session from the list and click <guibutton>Remove</guibutton>.</para>
<para>Do not show any users. This is the most secure setting, since an attacker would then have to guess a valid login name as well as a password. It's also the preferred option if you have more than a handful of users to list, or the list itself would become unwieldy.</para>
<para>Independently of the users you specify by name, you can use the <guilabel>System UIDs</guilabel> to specify a range of valid <acronym>UID</acronym>s that are shown in the list. By default user id's under 1000, which are often system or daemon users, and user id's over 65000, are not shown.</para>
<para>You can also enable the <guilabel>Sort users</guilabel> checkbox, to have the user list sorted alphabetically. If this is disabled, users will appear in the order they are listed in the password file.</para>
<para>If you choose to show users, then the login window will show images (which you select), of a list of users. When someone is ready to login, they may select their user name/image, enter their password, and they are granted access. </para>
<para>You can configure the admin picture here, for each user on the system. Depending on the order selected above, users may be able to override your selection.</para>
<para>If you choose not to show users, then the login window will be more traditional. Users will need to type their username and password to gain entrance. This is the preferred way if you have many users on this terminal.</para>
<para>If <guilabel>Sort users</guilabel> is selected, then the list of users will be sorted alphabetically in the login window. If unchecked, users will be listed in the same order as they are on this page. If <guilabel>Show users</guilabel> is not checked, this has no effect.</para>
<listitem><para>Show only selected users: If this option is selected, only the users contained in the list labelled <guilabel>Selected Users</guilabel>, will be displayed in the login window. If <guilabel>Show users</guilabel> is not checked, this has no effect.</para></listitem>
<listitem><para>Show all users but no-show users: If this option is selected, all users will be listed, <emphasis>except</emphasis> those users contained in the list entitled <guilabel>No show users</guilabel>. If <guilabel>Show users</guilabel> is not checked, this has no effect. </para></listitem>
<para>The top rightmost listbox shows the selected users and the bottom rightmost listbox shows the users we do not want displayed in the login window.</para>
<para>To move a user from one listbox to another you click on the username in the listbox and click <guibutton>>></guibutton> to move the user from the leftmost box the the rightmost box or <guibutton><<</guibutton> to move the user from the rightmost box to the leftmost box.</para>
<note><para>This section of the manual only applies if <guilabel>Show users</guilabel> is selected. If it is not, this image box has no effect.</para></note>
<para>Every user on the system can be represented by an image. The image for each user is kept in a file called <filename>$<envar>TDEDIR</envar>/share/apps/tdm/pics/users/$<envar>USER</envar>.xpm</filename>. If there is no such file for a particular user, the file <filename>$<envar>TDEDIR</envar>/share/apps/tdm/pics/users/default.xpm</filename> will be used instead.</para>
<para>To assign a new image to a user just select the user in one of the listboxes and either drop an imagefile on the image button to the right or click on the image button and select a new image from the image selector.</para>
<para>If no user is currently selected you will be asked if you want to change the default image.</para>
<para>The replacement is performed by a &konqueror; process so if the imagefile already exists you will be prompted by &konqueror; if you want to replace it. If you confirm the image will be replaced - you will <emphasis>NOT</emphasis> have to press the <guibutton>Apply</guibutton> button.</para>
<para>In the <guilabel>convenience</guilabel> tab you can configure some options that make life easier for lazy people, like automatic login or disabling passwords.</para>
<important><para>Please think more than twice before using these options. Every option in the <guilabel>Convenience</guilabel> tab is well-suited to seriously compromise your system security. Practically, these options are only to be used in a completely non-critical environment, ⪚ a private computer at home. </para></important>
<para>Automatic login will give anyone access to a certain account on your system without doing any authentication. You can enable it using the option <guilabel>Enable auto-login</guilabel>.</para>
<para>Using this feature, you can allow certain users to login without having to provide their password. Enable this feature using the <guilabel>Enable password-less logins</guilabel> option.</para>
<para>Below this option you'll see a list of users on the system. Enable password-less login for specific users by checking the checkbox next to the login names. By default, this feature is disabled for all users.</para>
<important><para>Again, this option should only be used in a safe environment. If you enable it on a rather public system you should take care that only users with heavy access restrictions are granted password-less login, ⪚ <systemitem>guest</systemitem>.</para></important>
<para>The <guilabel>Automatically login after X server crash</guilabel> option allows you to skip the authentication procedure when your X server accidentally crashed.</para>
<para>You can also choose which user is <quote>preselected</quote> when &tdm; starts. The default is <guilabel>None</guilabel>, but you can choose <guilabel>Previous</guilabel> to have &tdm; default to the last successfully logged in user, or you can <guilabel>Specify</guilabel> a particular user to always be selected from the list. You can also have &tdm; set the focus to the password field, so that when you reach the &tdm; login screen, you can type the password immediately.</para>
<para>This chapter assumes that your system is already configured to run the X Window System, and that you only need to reconfigure it to allow graphical login.</para>
<para>The fundamental thing that controls whether your computer boots to a terminal prompt (console mode) or a graphical login prompt is the default runlevel. The runlevel is set by the program <application> <ulink url="man:init">/sbin/init</ulink></application> under the control of the configuration file <filename>/etc/inittab</filename>. The default runlevels used by different &UNIX; systems (and different &Linux; distributions) vary, but if you look at <filename>/etc/inittab</filename> the start of it should be something like this:</para>
<screen># Default runlevel. The runlevels used by RHS are:
<para>All but the last line of this extract are comments. The comments show that runlevel 5 is used for X11 and that runlevel 3 is used for multi-user mode without X11 (console mode). The final line specifies that the default runlevel of the system is 3 (console mode). If your system currently uses graphical login (for example, using &xdm;) its default runlevel will match the runlevel specified for X11.</para>
<para>The first step in configuring your system is to ensure that you can start &tdm; from the command line. Once this is working, you can change your system configuration so that &tdm; starts automatically each time you reboot your system.</para>
<para>To test &tdm;, you must first bring your system to a runlevel that does not run &xdm;. To do so, issue a command like this:</para>
<para>Instead of the number <option>3</option> you should specify the appropriate runlevel for console mode on your system.</para>
<para>If your system uses Pluggable Authentication Modules (<abbrev>PAM</abbrev>), which is normal with recent &Linux; and Solaris systems, you should check that your <abbrev>PAM</abbrev> configuration permits login through the service named <literal>kde</literal>. If you previously used &xdm; successfully, you should not need to make any changes to your <abbrev>PAM</abbrev> configuration in order to use &tdm;. <filename>/etc/pam.conf</filename> or <filename>/etc/pam.d/kde</filename>. Information on configuring <abbrev>PAM</abbrev> is beyond the scope of this handbook, but <abbrev>PAM</abbrev> comes with comprehensive documentation (try looking in <filename>/usr/share/doc/*pam*/html/</filename>).</para>
<para>Now it's time for you to test &tdm; by issuing the following command:</para>
<para>If you get a &tdm; login dialogue and you are able to log in, things are going well. The main thing that can go wrong here is that the run-time linker might not find the shared &Qt; or &kde; libraries. If you have a binary distribution of the &kde; libraries, make sure &tdm; is installed where the libraries believe &kde; is installed and try setting some environment variables to point to your &kde; and &Qt; libraries.</para>
<para>If you are still unsuccessful, try starting &xdm; instead, to make sure that you are not suffering from a more serious X configuration problem.</para>
<para>For &Mandrake;, the X11 runlevel in <filename>/etc/inittab</filename> invokes the shell script <filename>/etc/X11/prefdm</filename>, which is set up to select from amongst several display managers, including &tdm;. Make sure that all the paths are correct for your installation.</para>
<listitem><para>For FreeBSD, edit <filename>/etc/ttys</filename> and find the line like this: <screen>ttyv8 "/usr/X11R6/bin/xdm -nodaemon" xterm off secure</screen> and edit it to this: <screen>ttyv8 "/usr/local/bin/tdm -nodaemon" xterm on secure</screen>
<para>At this stage, you can test &tdm; again by bringing your system to the runlevel that should now run &tdm;. To do so, issue a command like this:</para>
<para>Instead of the number <option>5</option> you should specify the appropriate runlevel for running X11 on your system.</para>
<para>The final step is to edit the <parameter>initdefault</parameter> entry in <filename>/etc/inittab</filename> to specify the appropriate runlevel for X11.</para>
<warning><para>Before you make this change, ensure that you have a way to reboot your system if a problem occurs. This might be a <quote>rescue</quote> floppy-disk provided by your operating system distribution or a specially-designed <quote>rescue</quote> floppy-disk, such as <literal>tomsrtbt</literal>. Ignore this advice at your peril.</para></warning>
<para>When you reboot your system, you should end up with the graphical &tdm; login dialogue.</para>
<para>If this step is unsuccessful the most likely problem is that the environment used at boot time differs from the environment that you used for testing at the command line. If you are trying to get two versions of KDE to co-exist, be particularly careful that the settings you use for your <envar>PATH</envar> and <envar>LD_LIBRARY_PATH</envar> environment variables are consistent, and that the startup scripts are not over-riding them in some way.</para>
<para>The main dialogue box for &tdm; includes a <guilabel>Session Type:</guilabel> drop-down box, which allows you to select a window manager to use for your session. This chapter describes the changes that you must make to your configuration files in order to support this feature.</para>
<para>The options that appear in the <guilabel>Session Type:</guilabel> drop-down box are <ulink url="TDM">configured</ulink> by entries in the <literal>TDM</literal> section of &tdmrc;.</para>
<para>When you log in using &tdm;, the shell script <filename>Xsession</filename> is executed. The session type that you select is passed as a command-line argument. (<filename>Xsession</filename> can be found in <filename>/etc/X11/xdm/</filename> for Redhat and Mandrake, and in <filename>/usr/X11R6/lib/X11/xdm/</filename> for S.u.S.E.). Whilst debugging, you might find it helpful to add this line to <filename>Xsession</filename>:</para>
<para>How you proceed now depends upon how your system usually starts up window managers. Here are two different approaches, with examples of the changes that you must make:</para>
<listitem><para>The window manager is started by commands within <filename>Xsession</filename>. In this case, you can add a case statement to start the appropriate window manager. Linux Mandrake uses this approach; here is an extract from <filename>Xsession</filename>:</para>
<listitem><para>The window manager is started by another script that is invoked by <filename>Xsession</filename>. In this case you must ensure that the parameter passed to <filename>Xsession</filename> is passed on to that other script. For example, if the window manager is started like this:</para>
<para>Having made this change, you must trace your way through the startup to find the place where the window manager is started. One approach uses <filename>xinitrc</filename> to start the window manager; this allows a system-wide file <filename>/etc/X11/xinit/xinitrc</filename> or a user-specific file <filename>$HOME/.xinitrc</filename> to be used. If you edit <filename>$HOME/.xinitrc</filename>, you may want to save a copy in <filename>/etc/skel</filename>, so that it will be automatically generated in every user account you create from now on. Here is an example <filename>xinitrc</filename> for a system using this approach:</para>
<para>&XDMCP; is the Open Group standard, the <quote>X Display Manager Control Protocol</quote>. This is used to set up connections between remote systems over the network.</para>
<para>&XDMCP; is useful in multiuser situations where there are users with workstations and a more powerful server that can provide the resources to run multiple X sessions. For example, &XDMCP; is a good way to reuse old computers - a Pentium or even 486 computer with 16 Mb RAM is sufficient to run X itself, and using XDMCP such a computer can run a full modern &kde; session from a server. For the server part, once a single &kde; (or other environment) session is running, running another one requires very few extra resources.</para>
<para>However, allowing another method of login to your machine obviously has security implications. You should run this service only if you need to allow remote X Servers to start login sessions on your system. Users with a single &UNIX; computer should not need to run this.</para>
<para>Since &tdm; is descended from &xdm;, the <ulink url="man:xdm">xdm man page</ulink> may provide useful background information. For X-related problems try the man pages <ulink url="man:X">X</ulink> and <ulink url="man:startx">startx</ulink>. If you have questions about &tdm; that are not answered by this handbook, take advantage of the fact the &tdm; is provided under the terms of the <abbrev>GNU</abbrev> General Public Licence: look at the source code. </para>
<chapter id="credits"><title>Credits and Licence</title>
<para>&tdm; is derived from, and includes code from, &xdm; (C) Keith Packard, MIT X Consortium.</para>
<para>&tdm; 0.1 was written by Matthias Ettrich. Later versions till &kde; 2.0.x were written by Steffen Hansen. Some new features for &kde; 2.1.x and a major rewrite for &kde; 2.2.x made by Oswald Buddenhagen.</para>
<para>Other parts of the &tdm; code are copyright by the authors, and licensed under the terms of the <ulink url="common/gpl-license.html">GNU GPL</ulink>. Anyone is allowed to change &tdm; and redistribute the result as long as the names of the authors are mentioned.</para>
<para>&tdm; requires the Qt library, which is copyright Troll Tech AS.</para>
<para>Documentation contributors: <itemizedlist>
<listitem><para>Documentation written by Steffen Hansen <email>stefh@dit.ou.dk</email></para></listitem>
<listitem><para>Documentation extended by Gregor Zumstein<email>zumstein@ssd.ethz.ch</email>. Last update August 9, 1998</para></listitem>
<listitem><para>Documentation revised for KDE 2 by Neal Crook<email>nac@forth.org</email>. Last update August 6, 2000</para></listitem>
<listitem><para>Documentation extended and revised for KDE 2.2 by Oswald Buddenhagen<email>ossi@kde.org</email>. Last update August, 2001</para></listitem>
</itemizedlist></para>
<para>Documentation copyright Steffen Hansen, Gregor Zumstein, Neal Crook and Oswald Buddenhagen. This document also includes large parts of the &xdm; man page, which is (C) Keith Packard.</para>
<para>Conversion to British English: John Knight <email>anarchist_tomato@herzeleid.net</email></para>
<para>&tdm; is part of the KDE project. The various component parts of the KDE project are broken into sections, called packages. &tdm; is part of the package called tdebase. You can get KDE source code from various Linux and BSD distribution CDs, or by download from <ulink url="http://www.kde.org">www.kde.org</ulink> or its mirrors. If you have an out-of-date source code tree, you can use one of the KDE cvsup servers to bring it up-to-date whilst using minimal network bandwidth. </para>
<para>Before building tdebase, you must have built and installed (in this order) version 2 of the qt library and the KDE packages tdesupport (optionally) and tdelibs.</para>
<para>In order to build any of the above, you must already have the X Window System installed, together with a C++ compiler. If are you building from CVS you will also need the GNU configuration tools <application>automake</application> and <application>autoconf</application>.</para>
<para>If the last few paragraphs seemed like a foreign language, then either you have strayed into an Inappropriate Area of this handbook, or you are about to undergo a Great Learning Experience.</para>
<para>If you managed to satisfy all of the prerequisites, you are unlikely to have any problems with building and installing tdebase. &tdm; is installed in your <filename>$TDEDIR/bin</filename> folder.</para>
<note><para><command>make <option>install</option></command> will <emphasis>not</emphasis> overwrite your previous &tdm; config files including &tdmrc;.</para></note>
