Path: utzoo!attcan!uunet!wugate!wuarchive!swbatl!texbell!vector!chip From: chip@vector.Dallas.TX.US (Chip Rosenthal) Newsgroups: news.newusers.questions Subject: Re: All these title lines! Keywords: perplexed Message-ID: <321@vector.Dallas.TX.US> Date: 30 Jul 89 04:35:51 GMT References: <14733@dartvax.Dartmouth.EDU> Reply-To: chip@vector.Dallas.TX.US (Chip Rosenthal) Organization: Dallas Semiconductor Lines: 114 jarvis@northstar.dartmouth.edu (Mark (Ninjabutler) Robinson) writes: >How can I fill in the empty titles 'Expires:', 'References:', 'Sender:', and >'Followup-To:', above, when I am posting to the net? Are they really >important? It is important that you (almost always) DO NOT fill in the "Expires:". Most times, use of this header is rude. More in a moment, but I want to make this point clearly at the outset. Second question first - "no". However, sometimes you might want to use some of them. I will describe these headers, so that you can decide when the circumstances arise whether or not to use them. How you go about adding these headers depends upon the news posting program you use. For example, the "Pnews" program gives you these headers with blank values. You can just fill in the values. The "postnews" program doesn't provide such a boiler-plate, and you will need to manually add them in with the other headers it provides. Expires ======= Regularly (say nightly), every news administrator runs a program called "expire" on his or her system. This program searches out all the older news articles and deletes them. The local site administrator gets to specify exactly how long articles should hang around before being expired. In my case, I run a half-dozen different expires a night, expiring stuff nobody reads quickly, keeping other things around longer. An article which contains an "Expires:" header with a date value expires on that date, and not when I want it to. Therefore, flagerant use of this line is rude, because you don't let me administer my system the way I want to. On the other hand, "Expires:" headers are often used justifiably. One place is "news.announce.newusers" so that the monthly informational messages hang around for a month. References ========== When you post a news article in response to somebody else's, your article is called a followup. The "References:" header points to the original article to which your refers. It does this by taking the value in the "Message-ID" field of the original message. You can have followups to followups, and in which case you can have "References:" headers with many references in them. Generally, when you hit "F" or "f" in your news reader, it automatically creates this line for you. You shouldn't ever have to worry about it. Unfortunately, most of the available news reading software isn't able to do anything with this header. If they did, theoretically you could easily follow through a discussion thread. However, this is complicated by the fact that a lot of software out there doesn't formulate the "References" header properly. Sender ====== Generally, you post your own news articles. But this isn't always the case. Maybe a friend wants to post a message from your account. Maybe a daemon runs on your machine which gateways messages into news. In both these cases, you don't want the "From:" line to reflect the owner of the computer account, but rather it should say who wrote the message. Therefore in these cases you would want to insert a "From:" line rather than take the usual one. The news software notices when the person in the "From" line isn't the owner of the account, and automatically inserts a "Sender" line to add some accountability. You should never insert a "Sender" line. Even if you do, the news software will wipe it out. Followup-To =========== Suppose you post a message in comp.lang.c saying that NULL should be "-1". Then suppose I post a followup saying that's silly. Then I go on to say "furthermore, it is stupid that XENIX defines NULL as (char *)0". Well, we are now starting to wander from a general c discussion to the XENIX implementation. Maybe it would be a good idea to get the XENIX folks involved. By default, any followup messages to mine will go to "comp.lang.c". However I can specify a "Followup-To:" header to make followups go somewhere else. The argument to this header is either a newsgroup name, or a comma delimited list of newsgroups. This purpose, redirecting followups to another newsgroup, is the most common use of the "Followup-To" field. There is one other use. Modern news software recognizes a magic value of "poster" in this field. This says that followups shouldn't be posted to USENET, but rather they should be mailed to the poster (i.e. author of that message). Older software won't recognize the meaning of "poster" but will instead try to post to a newsgroup called "poster". Since there is no such thing, the posting will fail with an error message, which is the same net result. In summary, you should never have to insert "References" and "Sender" fields. If they are appropriate, then your news software should do it automatically. You should probably never use an "Expires" header, in almost all cases to do so is rude. The "Followup-To" header, however, is something you might want to use from time to time if a discussion is wandering in a direction more suitable for a different newsgroup. There is a document entitled "Standard for Interchange of USENET Messages" which is part of the standard B2.11 USENET software distribution. This document formally defines all of the USENET headers. You should refer here for additional information. If you can find a file called "standard.mn" (maybe it's somewhere like /usr/src/news/doc), you can print off a copy of this by saying something like: nroff tmac.n standard.mn | lp -- Chip Rosenthal / chip@vector.Dallas.TX.US / Dallas Semiconductor / 214-450-5337 "I wish you'd put that starvation box down and go to bed" - Albert Collins' Mom