Looking up Online Documentation

You should familiarize yourself with an important source of information in CentOS Linux. Every so often, you see instructions that ask you to enter a Linux command. After a while, you are bound to get to the point at which you vaguely recall a command's name, but you cannot remember the exact syntax of what you are supposed to type. This is a situation in which the Linux online manual pages can come to your rescue.

Insider Insight

To try out the commands described in this section, you have to open a terminal window in GNOME. Select Main Menu>System Tools>Terminal (refer to Figure 7-2). This opens a terminal window in which you can type Linux commands.

You can view the manual page-commonly referred to as the man page-for a command by using the man command. (You do have to remember that command to access online help.) For example, to view the man page for the modprobe command, type the following command in a terminal window:

man modprobe

The man command then displays the help information page by page. Press the Spacebar to move to the next page. Press b to move backward by a page. To look for a specific word in the man page, press the forward slash, type the word, and press Enter. For example, to search for the word 'debug,' type /debug, and press Enter. When you finish reading the man page, press q to return to the Linux command prompt.

Having touted the usefulness of the online help pages, I must point out that the term Linux command refers to any executable file, ranging from a script file that contains other Linux commands to standard Linux executable programs. Although man pages exist for most standard programs, many programs do not have any online help. Nevertheless, whenever you are having difficulty recalling some command, it is worthwhile to use the man command to see whether any online help for that command exists.

If you do not want to read the full man page, you can use whatis to read a one-line summary of a command. For example, here's how you use whatis to see a brief description of the modprobe command:

whatis modprobe
modprobe             (8)  - high level handling of loadable module

The number (8) indicates the man page section where the modprobe command is listed. You should try the whatis command to view one-line descriptions of a few other commands.

You can use the shell's wildcard feature and the whatis command to explore the files in various system directories such as /bin, /sbin, /usr/sbin, /usr/bin, and so on. Simply change the directory to one of interest and type whatis * to view one-line descriptions of the programs in that directory. (whatis displays information for those programs for which such information is available.) For example, here is how you can explore the /sbin directory:

cd /sbin; whatis * | more
addpart: nothing appropriate
adsl-connect         (8)  - Shell script to manage a PPPoE link
adsl-setup           (8)  - Shell script to configure Roaring Penguin PPPoE clie
nt
adsl-start           (8)  - Shell script to bring up a PPPoE link
adsl-status          (8)  - Shell script to report on status of PPPoE link
adsl-stop            (8)  - Shell script to shut down a PPPoE link
agetty               (8)  - alternative Linux getty
arp                  (7)  - Linux ARP kernel module
arp                  (8)  - manipulate the system ARP cache
arping               (8)  - send ARP REQUEST to a neighbour host
arytst: nothing appropriate
avmcapictrl          (8)  - Add, reset or remove active AVM cards and load firmw
are
badblocks            (8)  - search a device for bad blocks
blockdev             (8)  - call block device ioctls from the command line
capiinit: nothing appropriate
cardctl              (8)  - PCMCIA card control utility
cardmgr              (8)  - PCMCIA device manager
chkconfig            (8)  - updates and queries runlevel information for system
services
clock                (3)  - Determine processor time
... rest of the output not shown ...

As you can see, the output is an alphabetic list of all programs in the current directory, along with the one-line descriptions where available. The whatis command displays a message saying nothing appropriate if there is no information available for a program.

The man and whatis commands are useful when you know the name of a command. If you do not know the exact name of a command, you can use the apropos command to search for a command by a keyword (or even a part of a word). For example, if you remember that the command contains the word probe, type the following apropos command to search:

apropos probe
modprobe             (8)  - high level handling of loadable modules
partprobe            (8)  - inform the OS of partition table changes
scanpci              (1x)  - scan/probe PCI buses

In this case, the search result shows three candidate commands, each with a brief description. You can then select the command that does what you want to do.

Insider Insight

If apropos displays a long list of commands that scroll by too fast for you to read, you can type apropos keyword | more to view the output one screen at a time.

Another form of online documentation you can refer to are the HOWTO files, which you can access by visiting the Linux Documentation Project (LDP) website http://www.redhat.com/mirrors/LDP/. (Click the earth icon on the GNOME Panel to launch the Mozilla Web browser.) On that Web page, you find (among other things) links to Frequently Asked Questions (FAQs) and HOWTOs. You can click the HOWTOs link and download (or read) HOWTO documents in several formats, including text and HTML. For example, if you click to view plain-text HOWTOs, the Web browser shows a list of HOWTO files.

Each HOWTO file contains information about some area of Linux, such as the hardware it supports or how to create a boot disk. As you scroll through the list, you find over 230 HOWTO files. Table 7-1 lists and briefly describes some of these HOWTO files. To view any of these files, click the name; the Web browser should display the full text file.

Insider Insight

Near the beginning of the list of HOWTO files, you find a folder named mini. Click that link to view a list of mini-HOWTOs, which cover many more narrowly focused topics.

Table 7-1: Some Linux HOWTO Files
HOWTO Filename	Contents
`ADSL-Bandwidth-Management-HOWTO`	How to configure a Linux router to more effectively manage outbound traffic on an ADSL modem or cable modem
`ATA-RAID-HOWTO`	How to install Linux on an Intel Pentium- compatible PC with an ATA RAID Controller and at least two hard disks
`AX25-HOWTO`	How to install and configure Linux to support the AX.25 packet radio protocol used by Amateur Radio Operators worldwide
`Accessibility-HOWTO`	How to make Linux accessible to persons with disabilities
`Adv-Routing-HOWTO`	How to do perform advanced routing with the IP routing capabilities built into Linux 2.2 and 2.4 kernels
`Apache-Compile-HOWTO`	How to compile the Apache Web server with the modules such as `mod_perl`, `mod_jserv`, and `mod_php`
`Apache-Overview-HOWTO`	An overview of the Apache Web server and other associated commercial and open source software
`Apache-WebDAV-LDAP-HOWTO`	How to set up an Apache-based WebDAV (Web enabled Distributed Authoring and Versioning) server that can authenticate against a LDAP server
`Assembly-HOWTO`	How to program in assembly language in Linux
`Authentication-Gateway-HOWTO`	How to set up an authentication gateway for wireless networks in Linux
`Bash-Prompt-HOWTO`	How to use the Bash shell (command processor)
`Belgian-HOWTO`	How to configure Linux for Belgian users
`BootPrompt-HOWTO`	A list of arguments that can be passed to Linux at boot time (at the `LILO boot:` prompt)
`Bootdisk-HOWTO`	How to create boot, root, and other utility disks for Linux
`C-C++Beautifier-HOWTO`	How to beautifully format C and C++ programs so that they are more readable
`Cable-Modem-HOWTO`	How to connect a Linux system to a cable modem or cable Internet service provider
`CD-Distributions-EN-HOWTO`	A list of English-language Linux distributions, with particular focus on commercial CD-ROM distributions
`CD-Writing-HOWTO`	How to record a CD-ROM using a CD Recorder installed in a Linux system
`CDROM-HOWTO`	How to install, configure, and use CD-ROM drives with Linux
`CVS-RCS-HOWTO`	How to set up CVS and RCS source code control systems
`Cable-Modem-Providers-HOWTO`	How to connect a Linux system with various cable modem-based Internet service providers
`Chroot-BIND HOWTO`	How to install and configure a BIND 8 name server in a secure manner
`Clone-HOWTO`	How to boot Linux using GRUB and save partition images to and restore from a TFTP server
`Cluster-HOWTO`	How to build and configure high-performance Linux computing clusters
`Config-HOWTO`	How to configure the most common applications in Linux
`DB2-HOWTO`	How to install DB2 Universal Database Version 7.1 for Linux
`DNS-HOWTO`	How to set up Domain Name Service (DNS) on a Linux system
`DOS-Win-to-Linux-HOWTO`	How to apply your DOS and Windows knowledge to the Linux environment
`DOS-to-Linux-HOWTO`	How to apply your knowledge of MS-DOS in Linux
`DSL-HOWTO`	How to set up and use high-speed DSL (Digital Subscriber Line) connections to the Internet
`DVD-HOWTO`	How to play DVD movies in Linux
`Diskless-HOWTO`	How to set up a diskless Linux system
`DocBook-Demystification-HOWTO`	Explanation of the DocBook markup system, used to write technical documentation for open-source projects hosted on Linux
`DocBook-OpenJade-SGML-XML-HOWTO`	How to set up OpenJade to process SGML/XML DocBook documents
`Emacs-Beginner-HOWTO`	How to use the Emacs editor in Linux
`Enterprise-Java-for-Linux-HOWTO`	How to set up an Enterprise Java environment on Linux
`Ethernet-HOWTO`	How to configure and use Ethernet network adapters with Linux
`Filesystems-HOWTO`	How to access various file systems
`Finnish-HOWTO`	How to set up Linux for the Finnish language. (Except for the initial paragraph, the HOWTO itself is in Finnish.)
`Firewall-HOWTO`	How to set up an Internet firewall on a Linux system
`Font-HOWTO`	A comprehensive source of information about using different types of fonts in Linux
`Framebuffer-HOWTO`	How to use framebuffer devices (an abstraction of graphics hardware) in Linux
`Francophones-HOWTO`	How to set up Linux for the French language. (This HOWTO is in French.)
`From-PowerUp-To-Bash-Prompt-HOWTO`	How Linux boots itself
`Ftape-HOWTO`	How to set up and use floppy tape drives (QIC-40, QIC-80, QIC-3010, and QIC-3020- compatible tape drives that connect to your PC through the floppy disk controller) in Linux
`Game-Server-HOWTO`	How to install, configure, and maintain servers for some popular multiplayer games such as Quake II and Quake III Arena
`GCC-HOWTO`	How to set up and use the GNU C compiler and development libraries in Linux
`German-HOWTO`	How to use Linux with the German character set. (This HOWTO is in German.)
`Glibc2-HOWTO`	How to install and use the GNU C Library version 2 (libc 6) on Linux systems
`Hardware-HOWTO`	A list of hardware known to work with Linux; and how to locate any necessary drivers
`Hebrew-HOWTO`	How to support the Hebrew character set in X Window System and text-mode screens
`Hellenic-HOWTO`	How to use Linux with the Greek character set. (This HOWTO is in Greek.)
`HighQuality-Apps-HOWTO`	How to create Linux applications that are highly integrated with the operating system and provides security and ease of use
`HOWTO-HOWTO`	How to write a HOWTO document
`HOWTO-INDEX`	Index of all HOWTOs
`Infrared-HOWTO`	How to use IrDA-compliant infrared devices in Linux (IrDA is a standard for infrared wireless communication at speeds ranging from 2400bps to 4Mbps)
`IngresII-HOWTO`	How to install the Ingres II Relational Database Management System on Linux
`Installation-HOWTO`	How to obtain and install Linux
`Intranet-Server-HOWTO`	How to use a Linux system in an Intranet that ties together Unix, Novell Netware, Windows NT, and Windows 95 systems
`IP-Masquerade-HOWTO`	How to enable the IP Masquerading feature on a Linux system
`IPCHAINS-HOWTO`	How to obtain, install, and configure the enhanced IP firewall chains software for Linux, including some ideas about how you might use the ipchains tool (ipchains replaces the older ipfwadm tool)
`IPX-HOWTO`	How to obtain, install, and configure various software that use the Linux support for IPX protocol (IPX is used by Novell NetWare)
`ISP-Hookup-HOWTO`	How to connect a Linux system to an Internet service provider (ISP) via a dial-up modem connection
`ISP-Setup-RedHat-HOWTO`	How to set up a CentOS Linux system for dial-in, virtual Web hosting, email, POP3, and FTP
`Italian-HOWTO`	How to set up Linux for the Italian language. (This HOWTO is in Italian.)
`Java-CGI-HOWTO`	How to develop and use Java programs in Linux
`Java-Decompiler-HOWTO`	How to decompile the Java class files
`Jaz-Drive-HOWTO`	How to use 1GB and 2GB Iomega Jaz drives in Linux
`KDE-GUI-Login-Configuration-HOWTO`	How to customize the KDE GUI login screen
`Kernel-HOWTO`	How to upgrade and rebuild the Linux kernel
`KernelAnalysis-HOWTO`	Description of the Linux kernel and how it works
`Keyboard-and-Console-HOWTO`	How to use various Linux utilities to configure the keyboard and the console (the text-mode screen)
`Kickstart-HOWTO`	How to use the CentOS Linux Kickstart system to install an identical version of Linux on a large number of systems
`Kiosk-HOWTO`	How to set up a Web-based kiosk using Linux, X, Netscape Navigator, and a trackball
`Kodak-Digitalcam-HOWTO`	How to get a Kodak digital camera to work in Linux
`Laptop-HOWTO`	How to install and use Linux on laptop computers
`LDAP-HOWTO`	How to install, configure, run, and maintain a Lightweight Directory Access Protocol (LDAP) server on a Linux system
`LDP-Reviewer-HOWTO`	How to review Linux Documentation Project (LDP) documentation
`LILO-crash-rescue-HOWTO`	How to recover from Linux system failures when you use the LILO boot loader
`Linmodem-HOWTO`	How to use Winmodems in Linux
`Linux+IPv6-HOWTO`	How to install, configure, and use IPv6 applications in Linux
`Linux+Win9x+Grub-HOWTO`	How to use the GRUB boot loader to support dual-booting of Windows and Linux
`Linux+XFS-HOWTO`	How to build a Linux system that uses the SGI XFS journaling file system
`Linux-Complete-Backup-and- Recovery-HOWTO`	How to back up a Linux system so as to be able to recover from a complete disk crash and how to make that recovery
`LinuxDoc+Emacs+Ispell-HOWTO`	How to use Emacs and `ispell` to write documents such as HOWTOs for the Linux Documentation Project
`Linux-Init-HOWTO`	Description of the Linux 2.4 kernel initialization sequence on IA-32 processors
`LVM-HOWTO`	How to build, install, and configure Logical Volume Manager (LVM) for Linux
`MIDI-HOWTO`	Description of hardware, software, and procedures needed to play and sequence using MIDI devices in Linux
`MILO-HOWTO`	How to set up and use the Miniloader (MILO) for Linux on Alpha AXP-based systems. (Just as LILO loads and starts Linux on Intel-based PCs, MILO loads Linux on Alpha systems.)
`Mail-Administrator-HOWTO`	How to perform system-administration tasks related to electronic mail (email) systems in Linux
`Mail-User-HOWTO`	Information for users of the email system
`Majordomo-MajorCool-HOWTO`	How to install Majordomo Mailing List Software and the MajorCool utility to manage Majordomo lists on Linux
`Masquerading-Simple-HOWTO`	How to set up IP masquerading using iptables
`Medicine-HOWTO`	Description of Linux software for medical sciences
`MIPS-HOWTO`	How to obtain and use the version of Linux for the MIPS processors from Silicon Graphics. (The MIPS processors are used in many systems, ranging from Silicon Graphics workstations to Nintendo 64 game consoles.)
`Modem-HOWTO`	How to select, connect, configure, and use modems in Linux
`Modem-Dialup-NT-HOWTO`	How to set up the modem to support dial-up networking with a remote server such as Windows NT Remote Access Server (RAS) or Linux
`Module-HOWTO`	How to create and use loadable kernel modules (LKMs) in Linux
`Mosix-HOWTO`	How to use openMosix, a software package that turns a network of Linux systems into a computer cluster
`MP3-HOWTO`	How to encode and play MP3 sound files in Linux
`Multi-Disk-HOWTO`	How to best use multiple disks and partitions in Linux
`Multicast-HOWTO`	Information about multicasting over TCP/IP networking
`Mutt-GnuPG-PGP-HOWTO`	How to configure Mutt-i, PGP, and various versions of GnuPG in order to set up a mail reader with encryption and digital-signing capabilities
`Net-HOWTO`	Description of all Linux Networking implementations
`NetMeeting-HOWTO`	How to configure Linux for interoperability with Microsoft NetMeeting
`Network-boot-HOWTO`	How to set up a Linux server to support booting diskless Linux clients using an IP network
`Network-Install-HOWTO`	How to install Linux over a local area network (LAN)
`Networking-Overview-HOWTO`	An overview of networking capabilities of Linux
`NFS-HOWTO`	How to set up an NFS (Network File System) server and client in Linux
`NIS-HOWTO`	How to configure NIS (Network Information Service) in Linux
`Online-Troubleshooting-HOWTO`	How to use resources available on the Internet to troubleshoot Linux-related problems
`Optical-Disk-HOWTO`	How to install and configure optical disk drives in Linux (includes detailed coverage of the Panasonic LF1000 PD Phase change optical drive with the SCSI-II interface)
`Oracle-7-HOWTO`	How to install and configure the Oracle Database Server on a Linux system
`Oracle-8-HOWTO`	How to install and get started with Oracle 8i Enterprise Edition for Linux
`Oracle8-on-RH7X-HOWTO`	How to install Oracle 8i, version 8.1.7 Enterprise Edition for Linux on a Red Hat 7.x system
`PalmOS-HOWTO`	How to use a PalmOS device (such as Palm III) with Linux
`Parallel-Processing-HOWTO`	How to use parallel processing approaches such as SMP (Symmetric Multiprocessing) Linux systems, clusters of networked Linux systems, and parallel execution using multimedia instructions (e.g., MMX), and attached (parallel) processors hosted by a Linux system
`PCI-HOWTO`	Information on Linux's support for the PCI (Peripheral Component Interconnect) bus architecture
`PCMCIA-HOWTO`	How to install and use PCMCIA (Personal Computer Memory Card International Association) Card Services in Linux
`PHP-HOWTO`	How to develop Web applications using PHP, a server-side HTML scripting language
`Plug-and-Play-HOWTO`	How to support Plug-and-Play (PnP) devices in Linux
`Polish-HOWTO`	How to set up Linux for the Polish language. (This HOWTO is in Polish.)
`Portuguese-HOWTO`	How to set up Linux for the Portuguese language. (This HOWTO is in Portuguese.)
`PostgreSQL-HOWTO`	How to set up and use the PostgreSQL database engine in Linux
`PPP-HOWTO`	How to set up and use Point-to-Point Protocol (PPP) networking in Linux
`Printing-HOWTO`	How to set up printing in Linux
`Printing-Usage-HOWTO`	How to use the print spooling system in Linux
`Program-Library-HOWTO`	How to create and use program libraries in Linux (aimed at programmers)
`Quake-HOWTO`	How to install, run, and troubleshoot Quake, QuakeWorld and Quake II in Linux (these are 3D action games developed by id Software)
`Querying-libiptc-HOWTO`	How to use the libiptc library included in the iptables package
`RedHat-CD-HOWTO`	How to make your own CDs from the CentOS Linux distribution that are equivalent to the ones commercially available from Red Hat
`Remote-Serial-Console-HOWTO`	How to set up Linux to support a terminal or modem attached to the serial port
`Root-RAID-HOWTO`	How to create a root-mounted RAID (Redundant Array of Inexpensive Disks) file system in Linux
`RPM-HOWTO`	How to use the Red Hat Package Manager (RPM) in Linux
`RTLinux-HOWTO`	How to set up and run RTLinux (real-time Linux)
`SCSI-2.4-HOWTO`	Description of the SCSI subsystem in the Linux 2.4 kernel
`SCSI-Generic-HOWTO`	Description of the SCSI Generic driver (`sg`) found in the Linux 2.4 kernel
`SCSI-Programming-HOWTO`	Information on programming the SCSI device driver in Linux (useful for programmers who want to add support for a new SCSI device in Linux)
`Secure-Programs-HOWTO`	How to write secure programs for Linux and UNIX systems
`Security-HOWTO`	An overview of security issues in a Linux system
`Security-Quickstart-HOWTO`	An overview of the basic steps required to secure a Linux system from intrusion
`Security-Quickstart-Redhat-HOWTO`	An overview of the basic steps required to secure a CentOS Linux system from intrusion
`Sentry-Firewall-CD-HOWTO`	How to set up a firewall using the Sentry Firewall CD (http://www.SentryFirewall.com/)
`Serbian-HOWTO`	How to configure Linux for Serbian users. (This HOWTO is in Serbian.)
`Serial-HOWTO`	How to set up serial communication devices in Linux
`Serial-Programming-HOWTO`	How to program the serial port in Linux
`Shadow-Password-HOWTO`	How to obtain, install, and configure the password Shadow Suite in Linux (password shadowing provides for more secure passwords than the ones stored in the `/etc/passwd` file)
`Slovenian-HOWTO`	How to configure Linux for Slovenian users. (This HOWTO is in Slovenian.)
`SMB-HOWTO`	How to use the Server Message Block (SMB) protocol, also called the NetBIOS or LAN Manager protocol, with Linux
`SMP-HOWTO`	Information on configuring Symmetric Multiprocessing (SMP) on Linux systems with multiple processors
`Snort-Statistics-HOWTO`	How to configure Snort version 1.8.3, a Network Intrusion Detection System (NIDS), to gather statistics about network packets
`Software-Building-HOWTO`	How to build and install UNIX software distributions in Linux
`Software-RAID-HOWTO`	How to use Software RAID (software-supported virtual redundant disks) in Linux
`Software-Release-Practice-HOWTO`	Describes the good software release practices of Linux Open Source projects
`Sound-HOWTO`	How to enable support for sound hardware in Linux
`Sound-Playing-HOWTO`	Lists many sound file formats and the applications that can be used to play sound in Linux
`Spanish-HOWTO`	How to configure Linux for Spanish-speaking users. (This HOWTO is in Spanish.)
`Speech-Recognition-HOWTO`	Description and use of automatic speech recognition software in Linux
`SRM-HOWTO`	How to boot an Alpha-based Linux system using the SRM (System Reference Manual) firmware, which is the firmware normally used to boot DEC Unix on Alpha
`SSL-Certificates-HOWTO`	How to manage a certificate authority (CA) and issue or sign certificates to be used for secure Web or secure email using Secure Sockets Layer (SSL)
`SSL-RedHat-HOWTO`	How to build a secure Apache Web server in CentOS Linux
`TclTk-HOWTO`	How to install, configure, and use the Tcl/Tk programming environment in Linux
`TeTeX-HOWTO`	How to install and use the teTeX TeX (pronounced tech as in technology) and LaTeX document formatting software in Linux
`Text-Terminal-HOWTO`	How to install and use text terminals (typically connected to multiport serial cards or a terminal server) with a Linux host
Thai-HOWTO	How to set up Linux for the Thai language
TimePrecision-HOWTO	How to maintain accurate date and time in Linux
Tips-HOWTO	Hints and tips to make Linux more useful and fun
UMSDOS-HOWTO	How to install and use the UMSDOS file system that lets you install Linux in an MS-DOS directory
Unicode-HOWTO	How to set up a Linux system so that it uses UTF-8 as text encoding
Unix-Internet-Fundamentals-HOWTO	Nontechnical description of how PCs, UNIX-like operating systems, and the Internet work
UPS-HOWTO	How to use an uninterruptible power supply (UPS) with Linux
USB-Digital-Camera-HOWTO	How to use in Linux a digital camera with Universal Serial Bus (USB) mass storage capabilities
Usenet-News-HOWTO	How to set up and access Usenet news in Linux
User-Authentication-HOWTO	How to secure user authentication in Linux
User-Group-HOWTO	How to establish and run a Linux User Group
UUCP-HOWTO	How to set up and use the Unix-to-Unix Copy (UUCP) software in Linux
VAR-HOWTO	Lists Linux Value Added Resellers (VARs)
Vim-HOWTO	How to set up and use the vim (Vi Improved) editor with color highlighting
Virtual-Services-HOWTO	How to support virtual services on a Linux system so that a single machine can recognize multiple IP addresses without multiple network cards
VME-HOWTO	How to run Linux on VMEbus systems
VMS-to-Linux-HOWTO	How to transition from VMS to Linux. (VMS is an operating system that runs on VAX systems from Digital Equipment Corporation.)
VoIP-HOWTO	Description of voice over IP (VoIP) system and software
VPN-HOWTO	How to configure a Linux system to support a virtual private network (VPN)
`VPN-Masquerade-HOWTO`	How to configure a Linux firewall to masquerade IPsec and Point-to-Point Tunneling Protocol (PPTP) traffic to support a virtual private network (VPN)
`WWW-HOWTO`	How to set up a World Wide Web (WWW) service in Linux
`WWW-mSQL-HOWTO`	How to use the mSQL database server with a Web server in Linux
`Winmodems-and-Linux-HOWTO`	How to get a Winmodem (which normally needs a Windows driver to work) working in Linux
`Wireless-HOWTO`	How to setup wireless networking in Linux
`XDMCP-HOWTO`	How to set up remote X terminals using X Display Manager (xdm, gdm, or kdm) and XDMCP (X Display Manager Control Protocol)
`XFree86-HOWTO`	How to install and configure the XFree86 (X Window System Version 11 Release 6-X11R6) in Linux
`XFree86-Video-Timings-HOWTO`	How to create a `modeline` in the X configuration file for a specific video card. (See Chapter 10 for a description of `modeline` and the format of the X configuration file.)
`XWindow-User-HOWTO`	How to configure the X Window environment for a Linux user
`Xinerama-HOWTO`	How to configure XFree86 Version 4.0 with multiple monitors and the Xinerama extension