\section{Usenet: Talking to the world without paying long-distance bills} \subsection{The Usenet\ldots} The Usenet (Users' Network) is a bulletin board shared among many computer systems around the world. Usenet is a logical network, sitting on top of several physical networks, including UUCP, BITNET, and the Internet. Sites on Usenet include many universities, private companies, and research organizations. Before using or learning to use the Usenet, it is helpful to understand some of the terminology used to describe it: \begin{description} \item[newsgroup:] A section of the net in which one particular topic is discussed. Newsgroups are named using a hierarchical tree structure quite similar in nature to the Unix\super{TM} file structure, but the net uses periods while Unix\super{TM} uses slashes. For example, discussion centering around the Apple Macintosh computer appears in a newsgroup entitled comp.sys.mac, while discussion about politics in general appears in talk.politics.misc. \item[article:] A message which someone has posted to the net. Other terms for an article include ``message'' and ``post.'' \item[subscribe:] In order to read a newsgroup, you subscribe to it. If you decide that you no longer wish to read the newsgroup, you unsubscribe from it. By default, you are asked for each new newsgroup if you want to subscribe to it.\footnote{This is the default for {\tt rn}, the program we'll be using here. The other programs have other defaults.} \item[{\tt .newsrc} file:] Your .newsrc file resides in your home directory and tells {\tt rn} which newsgroups you know about, to which ones you are subscribed and unsubscribed, and which articles in each newsgroup you have read. \item[{\tt KILL} files:] Despite the fact that the net usually tries to limit newsgroups in breadth of topics, you will still always find articles that you don't want to read in newsgroups that you DO want to read. {\tt rn} stores a {\tt KILL} file for each newsgroup, and these files instruct the program to get rid of certain articles before you even have to look at them. To ``kill'' (or ``junk'') an article is to make the system think you've already read it. \end{description} \subsection{Using {\tt rn} on Athena.} The SIPB currently supports several different interfaces to the Usenet. Among these are {\tt xrn}, an X-based interface, and {\tt GNUS}, a package for reading news within GNU Emacs. For more information on these, \footref{http://web.mit.edu/olh/Netnews/}{look at the on-line documentation,} or come by and ask us. In this document, however, we'll center on {\tt rn}. To use {\tt rn} you must add the {\tt sipb} locker by entering the command \verb+add sipb+ at your Athena prompt. You can put this command in your {\tt .environment} file to cause it to occur when you log in. {\tt rn} operates on three levels: the newsgroup selection level, the article selection level, and the paging level. Each level has its own set of commands, and its own help menu. At the {\em newsgroup selection} level (the top level), you may specify which newsgroup you want next, or read them in the default order, which is the order that the newsgroups occur in your {\tt .newsrc} file. (You will probably want to rearrange your {\tt .newsrc} file to put the most interesting newsgroups first. This can be done with the 'm' command on the newsgroup selection level, or by using a file editor such as {\tt emacs} to edit the file directly.) At the article selection level, you may specify which article you want next, or read them in the default order, which is either in order of arrival on your system, or by subject threads. At the paging level (the bottom level), {\tt rn} behaves much like the {\tt more} program. The most important command to remember in {\tt rn} is `h', for help. On any level, at any prompt, an `h' may be typed for a list of available commands. Furthermore, typing space to any question means to ``do the normal thing.'' You will know what that is because every prompt has a list of several plausible commands enclosed in square brackets. The first command in the list is the one which will be executed if you type a space. Some of the more important commands besides `h' and `space' are: \noindent ALL LEVELS: \begin{description} \item{{\tt u}} will unsubscribe from the current newsgroup. \item{{\tt c}} will ``catch up'' on the current newsgroup by marking all the messages in it read. \item{{\tt C-k}} will allow you to edit the KILL file for the current newsgroup. \end{description} \noindent NEWSGROUP LEVEL: \begin{description} \item{{\tt g {\em newsgroup}}} will go to the named newsgroup. If it is unsubscribed, the user will be asked if he or she wants to resubscribe to it. \end{description} \noindent ARTICLE OR PAGER LEVEL: \begin{description} \item{{\em number}} will go to the message with the given number. \item{{\tt k}} will kill all unread articles with the same subject line as the current article. \item{{\tt K}} will kill all unread articles with the same subject line as the current article and deposit this kill command in the KILL file for the current newsgroup so that it will be executed each time the newsgroup is accessed. \item{{\tt f {\rm and} F}} will post a follow-up article to the current article. If an upper-case F is used, the text of the current article will be embedded in the follow-up. \item{{\tt r {\rm and} R}} will respond to the current article through net mail. If an upper-case R is used, the text of the current article will be embedded in the mail letter. \item{{\tt \$}} will go to the end of the current newsgroup. Using the `r,' `R,' `f' or `F' after using the `\$' command command will allow you to post an article or write a mail letter from scratch. \end{description} These are only a few of the commands available in {\tt rn}. Rather then attempting to summarize everything that can be done with {\tt rn}, we recommend that you print out the manual page for the program and read it over. While it is not necessary for you to read the manual page to use {\tt rn}, it might be useful. \newline \vspace*{\baselineskip} If you just wish to view the man page on screen, issue the command \newline \vspace*{\baselineskip} {\tt \% man rn} \newline \vspace*{\baselineskip} Even if you choose not to read the man page now, it is a good idea to have it with you as a reference when you are first using {\tt rn}. \subsection{Hints and tips} \begin{description} \item[news.announce.newusers:] It is a good idea to read through news.announce.newusers before unsubscribing it. If you choose not to read the entire newsgroup, you should at least read the articles containing answers to frequently-asked questions and the Usenet Primer. Use \verb+g news.announce.newusers+ from the newsgroup level, then `=' to list the subjects, then enter a number to read the articles with the subjects you wish to read. \item[Using a {\tt .signature} file:] {\tt rn} and {\tt mh} disagree over what a {\tt .signature} file should do. While {\tt rrn} thinks it is something that should be placed at the end of a file, {\tt mh} thinks that it should be placed in the ``From:'' field of a mail message. Therefore, if you want to use a {\tt .signature} file with {\tt rn}, you will have to set a variable called ``Signature: '' in your {\tt \~{ }/.mh\_profile} file. Otherwise, {\tt mh} with look at your news posting signature, and do the wrong thing with it. Simply edit your {\tt .mh\_profile} and add a line like \begin{verbatim} Signature: Joe Random User \end{verbatim} to the end. You can then put a signature in {\tt \~{}/.signature} to be automatically added to the end of your news postings. \begin{sloppypar} \item[Including an article in your follow-up:] When you use the `F' command to post a follow-up article which contains the text of the original article, {\tt Pnews}, the program which handles such posting, gets very picky about how much new text you put into your article compared to how much you retain from the one to which you are responding. In most cases, you will edit the article you are including so that you only include the parts relevant to your followup (but be sure not to disrupt the {\tt References:\/} line in the header section.). But if you attempt to post an article which has more lines from the last article than lines you have added to it, {\tt Pnews} will reject the article. The way to avoid this is to fool {\tt Pnews} into thinking that lines from the original article are actually lines that you posted. Since the lines from the original article begin with `{\tt >}' by default, replacing the `{\tt >}' with another character fools {\tt Pnews}. The command sequence within emacs to do this is: {\tt M-x {\sl replace-string} C-q C-j > C-q C-j {\em string} }, where {\em string} is the character (or characters) with which you want to replace the `{\tt >}'. \end{sloppypar} \end{description}