Instant Linkbuilding Solutions
The sites and sources mentioned so far contain general kernel information, but memory management-specific sources are available too. A Linux-MM Web site at http www.linux-mm.org contains links to memory management-specific documentation and a linux-mm mailing list. The list is relatively light in comparison to the main list and is archived at http mail.nl.linux.org linux-mm .
From the viewpoint of TCP IP, if the data link and physical layers do their jobs, the details of data transmission are mostly transparent to Layer 3, the network layer, and the layers above Layer 3. If the lower layers don't do their job, the result will be dropped packets. If the data transmission is using the TCP transport protocol, effort will be made to retransmit dropped packets at the lower layers. However, as we will see in later chapters, TCP can't entirely compensate for low-quality links.
However, pay attention to the Graphics Cards section. Ideally, the details here should match your monitor and graphics card. SUSE Linux normally does a good job of choosing the correct resolution, but sometimes it gets that wrong. To fix this, click the relevant link under the Graphics Cards heading and choose a different option. For example, on one of my test PCs, a default resolution of 800x600 was suggested. I knew that the monitor could, in fact, support 1024x768. To fix this, I clicked the 800x600 link and chose a better resolution from the drop-down list that appeared. I also clicked Test the Configuration to check to make sure it all worked.
The applnk subdirectory ( share applnk) contains links to applications that will appear in the Personal submenu of your main menu. By default, this directory will be empty, and no Personal submenu will appear on your main menu. But as you install KDE-aware applications, they can add links so that an application will appear on the menu for easy launching.
The Link To Application entry is for launching applications. The Link To Location (URL) entry holds a URL address that you can use to access a Web or FTP site. The Link To Device submenu lets you create links to different kinds of devices, including CD-ROMs, hard disks, and cameras. Bear in mind that these are links only. You would rarely need to use them. Device icons that display on your desktop are now automatically generate directly by udev and HAL as needed (see Chapter 32).
The Tomboy Notes application allows you to create a series of notes to organize your thoughts. The neat thing about the notes is that you can link notes together based on linking words, much like links on web sites. You can write a note about remembering to mow the lawn next week and make a link in it to another note reminding you about the brand of fertilizer to use. You can also embed email and web links within your notes. Clicking the link automatically starts the email client or web browser and goes to that link. That really moves your note-taking to the next level
Basically, the purpose of a link is to make it easier to find files you need. You can create links for the operating system and for the program files that are used on that operating system, and they can make life easier for users as well. Imagine that some users are members of the group account, and you want them to create files in the directory home groups account that are readable by all the other group members. To do this, you can ask the users to change to the proper directory every time they want to save a file. As an alternative, you can create a link for each user in the user's home directory. Such a link can have the name account and can exist in the home directory of all the users who need to save work in the shared directory for the group account this makes it a lot easier for the users to save their files at the proper location.
Nautilus works much like most other file managers on Linux, Windows, or Mac OS. You can double-click directories to move into them, use the arrow buttons in the icon bar to move back to directories you've already seen or to move up in the hierarchy, drag and drop files between folders to move them, and so on. To copy a file or create a link, middle-click it and drag it to a location GNOME then asks if you want to move the file, copy it, or create a link. As with KDE's Konqueror, Nautilus treats the desktop as another folder, so you can move, copy, or create links to files on the desktop. If you want to create an icon on the desktop to launch a program, right-click on a free part of the desktop and pick New Launcher from the resulting context menu. Nautilus
This tag may be used when embedding HTML anchor or image tags (A or IMG tags) in a Javadoc comment to supply the root part of the documentation path. You should always use this instead of hard-coding the full URL, or a change in directory structure or server configuration might break all of your links.
The first section includes all elements that create links with other PCI data structures. node is a list element used to keep all buses on the global list mentioned above. parent is a pointer to the data structure of the higher-level bus. There may be just one parent bus. The subordinate or child buses must be managed on a linked list with children as the list head.
A point-to-point link does not seem like much of a network because only two endpoints are involved. However, most connections to WANs (wide area networks) go through point-to-point links, using wire cable, radio, or satellite links. The advantage of a point-to-point link is its simplicity Because only two systems are involved, the traffic on the link is limited and well understood. A disadvantage is that each system can typically be equipped for only a small number of such links it is impractical and costly to establish point-to-point links that connect each computer to all the rest.
A wide area network (WAN) covers a large geographic area. In contrast, the technologies (such as Ethernet) used for LANs were designed to work over limited distances and for a certain number of host connections. A WAN may span long distances over dedicated data lines (leased from a telephone company) or radio or satellite links. Such networks are often used to interconnect LANs. Major Internet service providers rely on WANs to connect to their customers within a country and around the globe.
The Web links data across different sites on the Internet throughout the world. The Web originated in Europe at CERN research laboratories, and CERN remains the original Web server. An Internet site that operates as a Web server is known as a Web site. Such Web sites are often dedicated to specialized topics or institutions-for example, the Smithsonian Web site or the NASA Web site. These Web sites usually have an Internet address that begins with www , as in www.redhat.com, the Web site for Red Hat, Inc. Once connected to a Web site, you can use hypertext links to move from one Web page to another.
The Web browser's connection to the Web server ends after the server sends the document. When the user browses through the downloaded document and clicks another hypertext link, the Web browser again connects to the Web server named in the hypertext link, downloads the document, ends the connection, and displays the new document. That's how the user can move from one document to another with ease.
To create a symbolic link to an existing file or directory, choose Make Link from the context menu. A symbolic link to the original item is created, with the text link to prepended to the original filename. The results of selecting the Make Link item can be seen in Figure 11.12.
Some of the main features of NSS are complete integration with eDirectory, extended Access Control Lists (ACLs), rights inheritance and filtering, support for multiple name spaces, and much, much more. Many of those capabilities are only possible through an NSS feature known as a backlink. With NSS, each file or directory is backlinked to the parent directory. This means that not only does the parent know what objects are beneath it, but the child also knows what parent directories are above it. This feature is unique to NSS and offers several powerful capabilities. One benefit of this is visible when browsing directories with varying permissions. In non-NSS filesystems, all directories are visible even if you do not have permission to enter the directory. With NSS, backlinks are used to ensure directory visibility is confined to just the directories you have access to. Another benefit is seen when assigning permissions. To provide access to a file several levels deep in a directory...
To enable the mod_userdir module, as well as other installed modules that are not enabled by default, you need to create links from the appropriate .load and .conf files in the etc apache2 mods-available directory to the mods-enabled directory. In Ubuntu, you can do this with the a2enmod command and restart the server as follows
The Bancos Trojan is a nasty piece of code that can steal passwords by masquerading as an interface for certain banks in Brazil. (See the symantec.com web link in the reference field in the Snort rule below for more information.) The Bleeding Snort project developed the signature, which can be found in the bleeding-all.rules file in the fwsnort sources. This signature is more complex than the previous Nmap execution signature because it requires the two application content matches shown in bold
Apache handles the virtual host features using a separate configuration file for each defined virtual host. These files are located in the etc apache2 sites-available and etc apache2 sites-enabled folders. As you can probably guess from the discussion on modules, the sites-available folder contains virtual host definitions, while the sites-enabl ed folder contains links to the virtual hosts that are enabled. This feature allows you to create a virtual host file ahead of time but not enable it until you're ready.
Using a connection-tracking mechanism to keep established TCP connections open provides an elegant solution for long-running TCP sessions, but what about short-lived connections such as those that transfer HTTP data over the Web8 or SMTP data between mailservers It would be inconvenient to generate a new SPA packet for every web link a user wishes to view this problem is compounded by the fact that every link is transferred over a separate TCP connection. In general, SPA is not well suited to protect such services.
Click Add Link to manually link to a site. Use the edit boxes to specify the Universal Resource Indicator (URI), the real name of the site, and a description. Create categories for your links in the Link Categories page and specify them for each link. You can also offer a more detailed description of your relationship with the site you're linking to.
Linux allows you to create links between files that look and work like normal files for the most part. Moreover, it allows you to make two types of links, known as hard links and symbolic links (symlinks). The difference between the two is crucial, although it might not be obvious at first
NOTE Because prices and services can vary so widely, I recommend that you shop around for a domain registrar. The Internet Corporation for Assigned Names and Numbers (ICANN) maintains a list of accredited registrars at The list contains links to registrar sites and a list of the TLDs that they support.
This database is searchable, either via keyword or full text. Besides German and English, the database exists in French, Spanish, Czech, and Hungarian (Magyar). The Online Support menu on the main support page links to some interesting HOWTO documents, showing you step by step how to handle issues great and small, from partitioning your hard drive to comparing HTML editors to encrypting email.
Why is Google (named after a math number) so powerful You can get a quick overview from the Google folks at http www.google.com technology . Part of its success is because of great algorithms, good programming, and simple interface design but most users really seem to appreciate Google's uncanny capability to provide links to what you are looking for in the first page of a search return. Google's early success was also assured because the site ran its search engine on clusters of thousands of PCs running a version of Red Hat Linux It is also rumored that an Ubuntu-based distribution is in use on desktops at Google, with the claimed moniker of Goobuntu.
Following the unexpected shutdown, Wndows runs its ScanDisk program over your entire hard drive, checking for both bad disk sectors and reestablishing where every file snippet is physically located on the disk. Because broken links might occur, you may have orphaned clusters, a common problem that will result in a loss of data.
This loop performs the same checks to ignore broken links and files lingering from previous RPM package installations. Also, the rc script will not attempt to start a daemon if its lock files in the var lock subsys directory exist, indicating that the daemon is already running.
Allows for the creation ofsymbolic links within the package build directories. The links are guaranteed to be policy-conformant. In addition to the command line, debian .links can specify pairs of links to be created. The file debian links contains links to be created in all packages.
Figure 13-8 demonstrates a WSDL file that provides the functionality to search for multiple names within an example web service. Understanding the key sections of a WSDL file is critical when hacking a web service. The types section defines the format of the available methods, including the corresponding parameters and types. The SearchRequest method requires two elements, Name and Count of type String and Integer, respectively. The message sections define the method names and types, such as input or output, which correspond to request and response. The service section defines the web service name and the address where the web service is located. This is the URL used to actually access the web service. The other item to note is the definitions sections, which contains links to Simple Object Access Protocol (SOAP) schemas that can be used throughout the WSDL file.
Info pages are detailed usage instructions and program or command guides. This documentation is accessed via an emacs-type interface that supports hypertext links, and advanced navigation Within the info system, multiple individual pages of information make up the entire set of info pages for each specific application. These pages of information are referred to as nodes. You can page through nodes one at a time, or you can jump to specific pages through the use of hypertext links. For new users, this navigation can be challenging.
Go to the web page you want to save to your hard drive. Once there, open the Location menu and select Save As, which will open a dialog box. You will see that the filter is set to HTML files, and the location is the name of the web page you want to save. If you like, you can alter the name of the web page and save it as a file, as you learned in Chapter 3. Doing this will save the page itself to your hard drive, but images are files of their own and, unless they are embedded in the page, will appear as broken links in your local copy. Go to the web page you want to save to your hard drive. Once there, open the Location menu and select Save As, which will open a dialog box. You will see that the filter is set to HTML files, and the location is the name of the web page you want to save. If you like, you can alter the name of the web page and save it as a file, as you learned in Chapter 3. Doing this will save the page itself to your hard drive, but images are files of their own and,...
More complex programs can tax the man page format, so the info help format was created. These pages, created with a version of the TeX document formatting system, include a hierarchical structure, hypertext links for easy navigation between documents, and keyboard and mouse navigational tools. The first time you use info (often when looking for help in the Emacs text editor), it can be a little overwhelming, but it is not too hard to deal with after you have a feel for it. Read the info tutorial (type info info) to learn more.
The far left side of the top panel contains the menu area. The menu area contains links that allow you easy access to all of the applications and utilities installed on the Ubuntu system. There are three top-level menu links that appear directly on the top panel The Applications menu Contains links that launch application programs available on the Ubuntu system. The Places menu Contains links to locations in the Ubuntu virtual filesystem, plus links to additional hard drives, floppy disks, CD DVD drives, and USB drives, and for connecting to remote filesystems. The System menu Contains links to utilities for changing user and system settings.
The remainder of the screen is the desktop. Here, you can place directories, files, or programs. You can create them on the desktop directly or drag them from a file manager window. A click-and-drag operation will move a file from one window to another or to the desktop. A click and drag with the ctrl key held down will copy a file. A click-and-drag operation with the middle mouse button (two buttons at once on a two-button mouse) enables you to create links on the desktop to installed programs. Initially, the desktop holds only an icon for your home directory. Clicking it opens a file manager window to that directory. A right-click anywhere on the desktop displays a desktop menu with which you can open new windows and create new folders.
The remainder of the screen is the desktop. Here, you can place directories, files, or programs. You can create them on the desktop directly or drag them from a file manager window. A click-and-drag operation with the middle mouse button enables you to create links on the desktop to installed programs. Initially, the desktop only holds an icon for your home directory. Clicking it opens a file manager window to that directory. A right- click anywhere on the desktop displays a desktop menu (see Table 8-1) with which you can open new windows, create new folders, and mount floppy disks and CD-ROMs.
You can create hard or soft links using the -I and -s options to cp, as noted in Table 5.2. You can also create links using the In command, which uses a syntax that's identical to that of cp. The two commands also share many options, including -b, -f, and -i. Ordinarily, In creates a hard link but passing it the -s option causes it to create a symbolic link. In either case, you can create links on any Linux-native filesystem, such as the Mi nix filesystem, ext2fs, ext3fs, ReiserFS, JFS, orXFS. The Rock Ridge extensions to ISO-9660 also support soft links, although some mkisofs options cause them to be ignored or converted into duplicate files. A few non-Linux filesystems support soft links, such as OS 2's High-Performance File System (HPFS). The soft links are encoded as HPFS Extended Attributes and aren't useable from OS 2. You can't create links on most other filesystems, including FAT, although you can create soft links that reside on Linux filesystems that point to files on...
In many cases the Linux file hierarchy encompasses several filesystems. Because each filesystem keeps separate control information (that is, separate inode tables or filesystem structures) for the files it holds, it is not possible to create hard links between files in different filesystems. A symbolic link can point to any file, regardless of where it is located in the file structure, but a hard link to a file must be in the same filesystem as the other hard link(s) to the file. When you create links only among files in your home directory, you will not notice this limitation.
If you intend to add printer support to your embedded system, I suggest you read up on Unix printer management from any of the good conventional Unix or Linux systems management books available. Running Linux by Welsh, Dalheimer, and Kaufman (O'Reilly) provides a good description of how printer setup is done in Linux when using LPD. For bleeding edge information regarding Linux printing, take a look at http www.linuxprinting.org , the main resource on the subject. On that same web site, you will find the Printing HOWTO, which contains extensive information about the different print-management packages, their operation, and relevant links.
In some cases, broken tunnels are difficult to debug. If we have access to the tunnel entry and exit nodes, then the situation isn't too bad. But if one of the tunnel nodes is outside our administrative control, then things can quickly become tedious and frustrating because we see the tunnel as a broken link-layer connection only.
This will ask you a number of questions. Usually, you can just press the Enter key in order to accept the defaults. Particularly, when asked whether you want to create links for OpenGL, say yes. This will install a compatible version. OpenGL is a library for fast 3D graphics applications that display 3D graphics often use it, other applications never do. If you plan to run any 3D graphics applications, you should enable this. The installer will also ask you whether you want a link to the rstart utility to be created. If you do not know what rstart is, you can safely say no here.
Click the Install button to the right of the selected package. If you would like to read more about the software package before installing it, first click on More Info. is will take you to a short description of the application, as well as a screenshot and a web link when available. If you wish to
The snull module creates two interfaces. These interfaces are different from a simple loopback in that whatever you transmit through one of the interfaces loops back to the other one, not to itself. It looks like you have two external links, but actually your computer is replying to itself.
HTTP stands for HyperText Transfer Protocol. The HyperText part refers to the fact that Web pages include hypertext links. The Transfer Protocol part refers to the standard conventions for transferring a Web page across the network from one computer to another. Although you really don't have to understand HTTP to set up a Web server or use a Web browser, taking a look at its workings does help you understand how the Web works.
While man is the most ubiquitous documentation format, info is much more powerful. It provides hypertext links to make reading large documents much easier and many features for the documentation writer. There are some very complete info documents on various aspects of Red Hat (especially the portions from the GNU project).
Many Linux distributions have Postfix built-in, so you may already have it installed on your system. If not, you can find prebuilt packages or compile it yourself from the source code. The Postfix home page (http www.postfix.org ) contains links to download both the source code ( Download ) and packages for different Linux distributions ( Packages and Ports ).
After the script variable is set, it replaces the filename of the script in usage and error messages. By using a variable that is derived from the command that invoked the script rather than a filename that is hardcoded into the script, you can create links to the script or rename it, and the usage and error messages will still provide accurate information.
You can obtain the source code using the coupon at the end of this book. As an alternative, you can use the following list, which contains links to where you can get the source code for all of the Linux distributions included with the book. In some cases, you need to choose a convenient mirror site from which to download the source code or use bittorrent
FrameMaker and FrameBuilder documents can be converted to HTML format with the tool FM2HTML. FM2HTML is a set of scripts that converts Frame documents to HTML while preserving hypertext links and tables. It also handles GIF files without a problem. Because Frame documents are platform-independent, Frame documents developed on a PC or Macintosh could be moved to a Linux platform and FM2HTML executed there. you may want to provide a hyperlink to. These utilities tend to go by a number of names, such as robot, spider, or wanderer. They are all programs that moves across the Web automatically, creating a list of Web links that you can access. (Spiders are similar to the Archie and Veronica tools for the Internet, although neither of these cover the Web.)
In documents that support hypertext-style linking (such as HTML), the reader would activate the link to jump to the labeled section. The name element inserts the section name, and exists for document formats that do not support hypertext links. The name element in this example would be rendered as an HTML hypertext link to the URL specified on the first line. To support documents that do not speak HTML, use the element because it will suppress generation of the URL in all formats except HTML
Phishing is an attack whereby a user is tricked into providing authentication credentials for an online account, such as for a bank, to an untrusted source. Typically this is accomplished by sending an official-looking email to users requesting that they access their online account and perform some urgent task in the interest of security, such as changing their password. (The irony here would almost be humorous were it not for the damaging effects of a successful phishing attack against a user.) A web link is provided that appears legitimate but is subtly crafted to point the user to a website controlled by the attacker that closely mimics the authentic website. Once phished users visit the site and enter their credentials, the attacker siphons off their account credentials. The innocuous wording feigns a cordial and helpful attitude ( several login attempts, and You do not have to change your password . . . ), and the web link is carefully crafted. The link contains a bit of embedded...
First are the basic File and Xtns menus. From File, you can open files or access dialog boxes, where you'll find the Brush, Pattern, Palette, and Gradient menus. These menus allow you to choose brush size and type, color, and gradients, and all are very intuitive. If you select Acquire from the File menu, you can use The GIMP to take screenshots as well. This works in almost exactly the same way as KSnapshot (see Chapter 7). The Xtns menu provides access to extension and module menus. These are for creating effects and are meant for advanced users. It is probably best to leave all of them at their default settings. The ever-popular Script-Fu (more about Script-Fu later) and direct web links to GIMP resources are also available from the Xtns menu.
Link Wheels for Dummies
The only thing you need to start a link wheel is CONTENT Articles and the mentioned pages at your money site to link to. But like anything in IM, building a link wheel is not an exact science. Feel free to build the link wheel the way it suits you. Learn more within this guide by downloading it today.