Newsgroups provide a distributed conferencing system that spans the globe. You can post articles — essentially e-mail messages to an entire group of people — and respond to articles others have posted.
Think of an Internet newsgroup as a gathering place — a virtual meeting place where you can ask questions and discuss various issues. (And best of all, everything you discuss is archived for posterity.) Internet newsgroups are similar to the bulletin board systems (BBSs) of the pre-Web age or the forums offered on online systems such as AOL and MSN.
To participate in newsgroups, you need access to a news server — your Internet service provider (ISP) can give you this access. You also need a newsreader. Luckily, Linux comes with software that you can use to read newsgroups. In this chapter, I introduce you to newsgroups and show you how to read newsgroups with a few of the newsreaders. I also briefly explain how you can read and search newsgroups for free from a few Web sites.
Nowadays another popular way to read summaries of Web sites and weblogs is to use a program that can accept RSS feeds. At the end of this chapter, I briefly describe what an RSS feed is and how you can use a program such as KDE Akregator to subscribe to RSS feeds and read them on your Linux system.
Understanding Newsgroups
Newsgroups originated in Usenet — a store-and-forward messaging network that was widely used for exchanging e-mail and news items. Usenet works like a telegraph in that news and mail are relayed from one system to another. In Usenet, the systems aren’t on any network; the systems simply dial up one another and use the UNIX-to-UNIX Copy Protocol (UUCP) to transfer text messages.
Although it’s a loosely connected collection of computers, Usenet works well and continues to be used because little expense is involved in connecting to it. All you need is a modem and a site willing to store and forward your mail and news. You have to set up UUCP on your system, but you don’t need a sustained network connection; just a few phone calls are all you need to keep the e-mail and news flowing. The downside of Usenet is that you can’t use TCP/IP services such as the Web, TELNET, or FTP with UUCP.
From their Usenet origins, newsgroups have now migrated to the Internet (even though the newsgroups are still called Usenet newsgroups). Instead of UUCP, the Network News Transfer Protocol (NNTP) now transports the news.
Although (for most of the online world) the news transport protocol has changed from UUCP to NNTP, the store-and-forward concept of news transfer remains. Thus, if you want to get news on your Linux system, you have to find a news server from which your system can download news. Typically, you can use your ISP’s news server.
Newsgroup hierarchy
The Internet newsgroups are organized in a hierarchy for ease of maintenance as well as ease of use. The newsgroup names help keep things straight by displaying this hierarchy.
Admittedly, these newsgroup names are written in Internet-speak, which can seem obscure at first. But the language is easy to pick up after a little bit of explanation. For example, a typical newsgroup name looks like this:
comp.os.linux.announce
This is a newsgroup for announcements (announce) about the Linux operating system (os.linux), and these subjects fall under the broad category of computers (comp). As you can see, the format of a newsgroup name is a sequence of words separated by periods. These words denote the hierarchy of the newsgroup. Figure 3-1 illustrates the concept of the hierarchical organization of newsgroups.
To understand the newsgroup hierarchy, compare the newsgroup name with the pathname of a file (for example, /usr/lib/X11/xinit/Xclients) in Linux. Just as a file’s pathname shows the directory hierarchy of the file, the newsgroup name shows the newsgroup hierarchy. In filenames, a slash (/) separates the names of directories; in a newsgroup’s name, a period (.) separates the different levels in the newsgroup hierarchy.
Figure 3-1: Newsgroups are organized in a hierarchy with many top-level categories.
In a newsgroup name, the first word represents the newsgroup category. The comp.os.linux.announce newsgroup, as mentioned, is in the comp category, whereas alt.books.technical is in the alt category.
Top-level newsgroup categories
Table 3-1 lists some of the major newsgroup categories. You find a wide variety of newsgroups covering subjects ranging from politics to computers. The Linux-related newsgroups are in the comp.os.linux hierarchy.
| Table 3-1 | Some Major Newsgroup Categories |
| Category | Subject |
| alt | Alternative newsgroups (not subject to any rules), ranging from the mundane to the bizarre |
| bionet | Biology newsgroups |
| bit | Bitnet newsgroups |
| biz | Business newsgroups |
| clari | Clarinet news service (daily news) |
| comp | Computer hardware and software newsgroups (includes operating systems such as Linux and Microsoft Windows) |
| ieee | Newsgroups for the Institute of Electrical and Electronics Engineers (IEEE) |
| k12 | Newsgroups devoted to elementary and secondary education |
| linux | Newsgroups devoted to Linux (includes a linux.redhat hierarchy) |
| misc | Miscellaneous newsgroups |
| news | Newsgroups about Internet news administration |
| rec | Recreational and art newsgroups |
| sci | Science and engineering newsgroups |
| soc | Newsgroups for discussing social issues and various cultures |
| talk | Discussions of current issues (think talk radio) |
This short list of categories is deceptive because it doesn’t tell you about the wide-ranging variety of newsgroups available in each category. The top-level categories alone number more than a thousand, but many top-level categories are distributed only in specific regions of the world. Because each newsgroup category contains several levels of subcategories, the overall count of newsgroups is close to 100,000! The comp category alone has close to 1,200 newsgroups.
Unfortunately, many newsgroups are flooded with spam, like your e-mail Inbox only worse because anyone can post anything on a newsgroup. Moderated newsgroups offer some relief. Anyone who wants to post on a moderated newsgroup must first submit the article to a moderator — a human being — who then decides whether to post or reject the article. You can reduce the spam overload by browsing moderated newsgroups whenever possible.
To browse newsgroup categories and get a feel for the breadth of topics covered by the newsgroups, visit the Google Groups Web site at http:// groups.google.com and click the Browse All of Usenet link. (You will need to click the Browse Group Categories link on the first page.)
Linux-related newsgroups
Typically, you have to narrow your choice of newsgroups according to your interests. If you want to know more about Linux, for example, you can choose one or more of these newsgroups:
- comp.os.linux.admin: Linux system administration (inactive).
- comp.os.linux.advocacy: Linux promotion.
- comp.os.linux.announce: Important announcements about Linux. This newsgroup is moderated, which means you must mail the article to a moderator, who then posts it to the newsgroup if the article is appropriate for the newsgroup.
- comp.os.linux.answers: Questions and answers about Linux. All the Linux HOWTOs are posted in this moderated newsgroup.
- comp.os.linux.development: Current Linux development work.
- comp.os.linux.development.apps: Linux application development.
- comp.os.linux.development.system: Linux operating system development.
- comp.os.linux.embedded: Running the Linux operating system on embedded hardware.
- comp.os.linux.hardware: Linux and various types of hardware.
- comp.os.linux.help: Help with various aspects of Linux (inactive).
- comp.os.linux.misc: Miscellaneous Linux-related topics.
- comp.os.linux.networking: Networking under Linux.
- comp.os.linux.portable: Running the Linux operating system on laptop computers and portable PCs.
- comp.os.linux.powerpc: Running the Linux operating system on PowerPC microprocessors.
- comp.os.linux.redhat: Red Hat Linux-related topics (inactive).
- comp.os.linux.setup: Linux setup and installation.
- comp.os.linux.x: Setting up and running the X Window System under Linux.
- comp.os.linux.xbox: Running Linux on the Xbox video game console.
- linux.debian: Moderated newsgroup about Debian GNU/Linux (inactive).
- linux.debian.news: Moderated newsgroup for news items about Debian GNU/Linux.
- linux.redhat: Red Hat Linux discussions.
You have to be selective about what newsgroups you read because keeping up with all the news is impossible, even in a specific area such as Linux. When you first install and set up Linux, you might read newsgroups such as comp.os.linux.answers, comp.os.linux.setup, comp.os.linux. hardware, and comp.os.linux.x (especially if you have problems with X). After you have Linux up and running, you may want to find out about only new things happening in Linux. For such information, read the comp. os.linux.announce newsgroup.
Although a number of newsgroups are currently inactive and not being added to, these groups can still be referenced and searched for help with specific questions.
Reading Newsgroups from Your ISP If you sign up with an ISP for Internet access, it can provide you with access to a news server. Such Internet news servers communicate by using the Network News Transfer Protocol (NNTP). You can use an NNTP-capable newsreader, such as KNode, to access the news server and read selected newsgroups. You can also read news by using Thunderbird. Using a newsreader is the easiest way to access news from your ISP’s news server.
My discussion of reading newsgroups assumes that you obtained access to a news server from your ISP. The ISP provides you with the name of the news server and any username and password needed to set up your news account on the newsreader you use.
To read news, you need a newsreader — a program that enables you to select a newsgroup and view the items in that newsgroup. You also have to understand the newsgroup hierarchy and naming conventions (which I describe in the “Newsgroup hierarchy” section, earlier in this chapter). In this section, I show you how to read news from a news server.
If you don’t have access to newsgroups through your ISP, you can try using one of the many public news servers that are out there. For a list of public news servers, visit Newzbot at www.newzbot.com. At this Web site, you can search for news servers that carry specific newsgroups.
Taking stock of newsreaders You can use one of several software packages to download and read newsgroups in Linux. Here are a few major newsreaders:
- Thunderbird: Thunderbird includes the ability to download news from an NNTP server. You can read newsgroups and post items to newsgroups. Xandros uses Thunderbird for mail and news.
- KNode: This is a newsreader for KDE that you can download from knode.sourceforge.net. Debian and SUSE provide KNode as the newsreader.
- Pan: Pan is a GUI newsreader that, according to the developer’s Web site (http://pan.rebelbase.com), “attempts to be pleasing to both new and experienced users.” You can download Pan for various Linux distributions from http://pan.rebelbase.com/download.
If you don’t find a newsreader in your Linux system, you can download and install any of these newsreaders easily in any of the Linux distributions. Often, you can locate the download site by a simple search at a search engine — just search for the word download followed by the name of the newsreader.
Reading newsgroups with Thunderbird You can browse newsgroups and post articles from Thunderbird, a mail and newsreader from the Mozilla project.
In many Linux distributions, the mail and news component of Thunderbird may not be installed. In that case, you have to download and install the Thunderbird mail and news component or use another newsreader. To download Thunderbird, visit www.mozillamessaging.com/thunderbird/.
When you’re starting to read newsgroups with Thunderbird for the first time, follow these steps to set up the news account:
- Choose Edit»Account Settings from the Thunderbird menu.A dialog box appears.
- Select the Account Actions option and then click Add Other Account.
The Account Wizard appears, as shown in Figure 3-2.
Figure 3-2: Thunderbird’s Account Wizard guides you through the newsgroup account setup. - Select the Newsgroup Account option and click Next.
- In the new screen that appears, fill in your identity information — name and e-mail address. Then click Next to move to the next screen.
- Enter your news server name and click Next.
- Enter a descriptive name of the newsgroup account and click Next.
- Click Finish to complete the newsgroup account setup.
The new newsgroup account now appears in the list of accounts on the left side of the Thunderbird window. Click the newsgroup account name, and the right side of the window displays the options for the newsgroup account.
Click the Manage Newsgroup Subscriptions option. Thunderbird starts to download the list of newsgroups from the news server. Don’t be surprised if this process takes considerable time — the number of newsgroups is vast, and the speed of your connection can slow the downloading of the list to a point where you begin to get frustrated.
If your ISP’s news server requires a username and password, you’re prompted for that information. After that, Thunderbird downloads the list of newsgroups and displays them in the Subscribe dialog box. (You can enter a search string in a text box to narrow the list.) When you find the newsgroups you want, click the check box to the right of their names and then click the Subscribe button to subscribe to these newsgroups, as shown in Figure 3-3. Then click OK to close the dialog box.
Figure 3-3: Indicate which newsgroups you want to subscribe to in this dialog box. After you subscribe to newsgroups, these newsgroups appear under the newsgroup account name on the left side of the Thunderbird window. You can then read a newsgroup using these steps:
- Click a newsgroup name (for example, comp.os.linux.announce).
- If prompted, enter your username and password.Some news servers require a username and password.
- Specify the number of headers (for example, 500) you want to download and click Download to proceed.Thunderbird downloads the headers from the newsgroup and displays a list in the upper-right area of the window.
- From the list of headers, click an item to read that article, as shown in Figure 3-4.
Figure 3-4: Click an article to read it in the lower-right part of the window.
To select other subscribed newsgroups, simply click the newsgroup’s name in the left side of the window.
Newsgroup subscriptions Unlike magazines or newspapers, newsgroups don’t require that you subscribe to them; you can read any available newsgroup on the news server.
The news server’s administrator may decide to exclude certain newsgroups, however; if they aren’t included, you can’t read them. The only thing that can be called subscribing is indicating the newsgroups you routinely want to read. The news server doesn’t receive any of this subscription information — the information is used only by the newsreader to determine what to download from the news server.
Posting news
You can use any newsreader to post a news article (a new item or a reply to an old posting) to one or more newsgroups. The command for posting a news item depends on the newsreader. For example, in the Thunderbird newsreader, you follow these steps to post an article:
- Click the Reply button on the toolbar to post a follow-up to a news item you’re reading. To post a new news article, click the Write button.A window appears where you can compose the message.
- Type the names of the newsgroups, just as you’d type the addresses of recipients when sending e-mail. Enter the subject and your message.
For this test posting, type ignore as the subject line and enter misc. test as the name of the newsgroup. Otherwise, any site that receives your article replies by mail to tell you the article has reached the site; that’s in keeping with the purpose of the misc.test newsgroup.
- After you finish composing the message, click Send on the toolbar.Thunderbird sends the message to the news server, which in turn sends it to other news servers, and soon it’s all over the world!
- To verify that the test message reaches the newsgroup, choose File»Subscribe. Then subscribe to misc.test newsgroup (that’s where you recently posted the new article).To subscribe, click the check box to the right of the group name and then click the Subscribe button.
- Look at the latest article or one of the most recent ones in misc.test to find the article you recently posted.
If you post an article and read the newsgroup immediately, you see the new article, but that doesn’t mean the article has reached other sites on the Internet. After all, your posting shows up on your news server immediately because that’s where you posted the article. Because of the store-and-forward model of news distribution, the news article gradually propagates from your news server to others around the world.
The misc.test newsgroup provides a way to see whether your news posting is getting around. If you post to that newsgroup and don’t include the word ignore in the subject, news servers acknowledge receipt of the article by sending an e-mail message to the address listed in the Reply To field of the article’s header.
Using KNode Debian and SUSE provide KNode as the default newsreader. Typically, you can start KNode by selecting Newsreader from the menu (look in the Internet applications); or choose Applications»Internet»KNode. If you don’t see a choice for Newsreader or KNode in the menus, type knode in a terminal window to start KNode.
When KNode runs for the first time, it displays the Configure KNode dialog box, as shown in Figure 3-5, through which you can configure everything you need to read newsgroups and post items to newsgroups.
Figure 3-5: Configure KNode from this dialog box.The left side of the dialog box displays all the items that you can configure, and the right side is where you enter the information for the item that you’ve selected on the left.
When the Configure KNode dialog box first opens, it prompts for your personal information. Enter your identification information, such as name, e-mail address, and organization — this information is used when you post a new item to a newsgroup.
Then, click Accounts on the left side (refer to Figure 3-5) and then click the Newsgroup Servers tab on the right side to set up information about the news server from which you’ll be reading news. Click Add in the Newsgroup Servers tab to display the dialog box shown in Figure 3-6, where you can enter the information about the news server. Your ISP should have provided you with the information needed to access the news server. If the news server requires a login name and a password, you must enter that information as well.
Figure 3-6: Enter information about the news server in this dialog box.After you set up the news account, the KNode window shows the name of the news server on the left. Right-click the server’s name and choose Subscribe to Newsgroups from the pop-up menu. A dialog box appears where you can subscribe to selected newsgroups (such as comp. os.linux.announce). The first time you access this menu, the list of newsgroups must be fetched. The KNode user interface is similar to many other mail and newsreaders, including Thunderbird.
Reading and Searching Newsgroups at Web Sites
If you don’t have access to newsgroups through your ISP, you can still read newsgroups and post articles to newsgroups at a number of Web sites. Some of them archive old news articles and provide good search capabilities, so you can search these sites for articles related to some question you may have.
The best parts about reading newsgroups through a Web site is that you don’t even need access to a news server and you can read news from your Web browser.
Table 3-2 lists Web sites that offer free access to Usenet newsgroups. To get a list of all Web sites that offer newsgroup access (including the ones that charge a fee), use Google (www.google.com) and type the search words usenet newsgroup access.
| Table 3-2 | Web Sites with Free Access to Usenet Newsgroups |
| Web Site | URL |
| Google Groups | http://groups.google.com |
| mail2web | http://usenet.mail2web.com |
| InterBulletin | http://news.interbulletin.com |
| Usenet Replayer | www.usenet-replayer.com |
One of the best places to read newsgroups, post articles, and search old newsgroup archives is Google Groups (Google’s Usenet discussion forums) on the Web at http://groups.google.com. At that Web site, you can select a newsgroup to browse and post replies to articles posted on various newsgroups.
The best part of Google Groups is the search capability. You already know how good Google’s Web search is; you get that same comprehensive search capability to locate newsgroup postings that relate to your search words. To search newsgroups, fill in the search form at http://groups.google.com and press Enter.
To browse newsgroups in Google Groups, ignore the search box and look at the list of high-level newsgroup categories such as alt, comp, and soc. Click the category, and you can gradually drill down to specific newsgroups. When viewing an article in Google Groups, you can click a link that enables you to post a follow-up to that article.
Reading RSS Feeds
RSS stands for Really Simple Syndication. RSS is a format for syndicating — gathering and making available — the content of Web sites, primarily newsoriented sites and blogs. The term blog is short for weblog — a frequently updated journal with thoughts, comments, and opinions of the blog’s creator. RSS can be used to provide any kind of information that can be broken down into discrete items and put into RSS format. Such RSS-formatted content is an RSS feed, and an RSS-aware program can check the feed periodically for changes, download new items, and make them available to the user.
The RSS format is a dialect of XML (eXtensible Markup Language). All RSS files conform to XML 1.0 specification.
Many versions of RSS are available, but three versions — 0.91, 1.0, and 2.0 — are in widespread use. Netscape designed RSS version 0.90 for gathering and displaying headlines from news sites. A simpler version, 0.91, was proposed, and UserLand Software picked up that version for use in its blogging product. At the same time, another noncommercial group had evolved RSS 0.90 into RSS 1.0, which is based on resource description format, or RDF (see www.w3.org/rdf). UserLand didn’t accept RSS 1.0 but instead continued evolving RSS 0.91 through versions 0.92, 0.93, and 0.94 and finally settled on RSS 2.0 (skipping 1.0 because that version number was already taken). Currently, many blogs and Web sites use RSS 0.91 for basic syndication (title, URL, and description), RSS 1.0 for readers that use RDF, and RSS 2.0 for advanced syndication with more metadata. (Think of metadata as data about data, which is what the RSS format provides: It provides data about other information, such as blogs and news.) RSS 1.0 files have an .rdf extension, whereas RSS 0.91 and 2.0 files have an .xml extension. However, all RSS files are text files that use XML tags.
Examining an RSS Feed
An RSS feed is a text file with XML tags that describe a Web site’s content. You typically use an automated program to periodically generate the RSS feed file, but you can prepare the RSS feed file using a text editor. It’s good to know what an RSS feed looks like, just so you can debug problems with the feed.
The specific details of an RSS feed depend on the version of RSS. The simplest feed is RSS 0.91, and here’s a typical RSS 0.91 feed:
<?xml version=”1.0” ?>
<!-- A comment line --->
<rss version=”0.91”>
<channel> <!--- This tag specifies general information about the feed--->
<title>Title of this feed</title>
<link>URL of this feed, for example, http://edulaney.typepad.com/</link>
<description>Brief description of feed</description>
<language>en-us</language>
<item>
<title>Title of this item</title>
<link>URL for this item</link>
<description>Description of this item</description>
</item>
. . . more items . . .
</channel>
</rss>
As you can see from that listing, an RSS feed includes a channel with a title, link, description, and language followed by a series of items, each of which has a title, link, and description.
The format is more verbose for RSS 1.0, which uses the RDF format. RSS 1.0 essentially provides the basic information that’s in RSS 0.91 and adds more details such as item-level authors, subject, and publishing dates, which RSS 0.91 doesn’t support.
Reading RSS Feeds
Many GUI programs are available for subscribing to RSS feeds and reading items from a feed. These programs are RSS aggregators because they can gather information from many RSS feeds and make everything available in a single place.
The two types of RSS aggregators are Web browser plug-ins and standalone programs. Browser plug-ins, such as NewsMonster (www.newsmonster. org), run in a Web browser so that the feeds appear in the Web browser. Standalone programs such as GNOME Straw (http://projects.gnome. org/straw) and KDE Akregator (http://akregator.kde.org) are complete GUI applications and usually look similar to other mail and newsreader programs.
Fedora and SUSE come equipped with the Akregator program, a standalone RSS feed aggregator. To run it, look for a link in the GUI desktop’s applications menu (choose Application»Internet»Akregator). If you don’t see Akregator listed, type akregator in a terminal window. In Debian, you can install Akregator by typing apt-get install akregator (after typing su to become root).
When Akregator first runs, it displays its main window without any RSS feeds. To subscribe to a feed, choose Feed»Add Feed from the menu or right-click All Feeds in the left pane of the window (see Figure 3-7) and select Add Feed from the pop-up menu. Then type the URL for the feed in the Add Feed dialog box and click OK. For example, to read Slashdot’s RSS feed, type http://slashdot.org/index.rss. The feed’s title appears in the left pane of the window. Click the feed title to view the items in this feed. Then you can click an item in the upper-right pane, and that item appears in the lower-right pane, as shown in Figure 3-7. You can add many different RSS feeds, organize them into folders, and browse them in Akregator.
Figure 3-7: You can organize and read RSS feeds in Akregator.
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