diff options
Diffstat (limited to 'RFC/rfc977.txt')
| -rw-r--r-- | RFC/rfc977.txt | 1539 |
1 files changed, 0 insertions, 1539 deletions
diff --git a/RFC/rfc977.txt b/RFC/rfc977.txt deleted file mode 100644 index 0f965c48..00000000 --- a/RFC/rfc977.txt +++ /dev/null @@ -1,1539 +0,0 @@ -
-
-Network Working Group Brian Kantor (U.C. San Diego)
-Request for Comments: 977 Phil Lapsley (U.C. Berkeley)
- February 1986
-
- Network News Transfer Protocol
-
- A Proposed Standard for the Stream-Based
- Transmission of News
-
-Status of This Memo
-
- NNTP specifies a protocol for the distribution, inquiry, retrieval,
- and posting of news articles using a reliable stream-based
- transmission of news among the ARPA-Internet community. NNTP is
- designed so that news articles are stored in a central database
- allowing a subscriber to select only those items he wishes to read.
- Indexing, cross-referencing, and expiration of aged messages are also
- provided. This RFC suggests a proposed protocol for the ARPA-Internet
- community, and requests discussion and suggestions for improvements.
- Distribution of this memo is unlimited.
-
-1. Introduction
-
- For many years, the ARPA-Internet community has supported the
- distribution of bulletins, information, and data in a timely fashion
- to thousands of participants. We collectively refer to such items of
- information as "news". Such news provides for the rapid
- dissemination of items of interest such as software bug fixes, new
- product reviews, technical tips, and programming pointers, as well as
- rapid-fire discussions of matters of concern to the working computer
- professional. News is very popular among its readers.
-
- There are popularly two methods of distributing such news: the
- Internet method of direct mailing, and the USENET news system.
-
-1.1. Internet Mailing Lists
-
- The Internet community distributes news by the use of mailing lists.
- These are lists of subscriber's mailbox addresses and remailing
- sublists of all intended recipients. These mailing lists operate by
- remailing a copy of the information to be distributed to each
- subscriber on the mailing list. Such remailing is inefficient when a
- mailing list grows beyond a dozen or so people, since sending a
- separate copy to each of the subscribers occupies large quantities of
- network bandwidth, CPU resources, and significant amounts of disk
- storage at the destination host. There is also a significant problem
- in maintenance of the list itself: as subscribers move from one job
- to another; as new subscribers join and old ones leave; and as hosts
- come in and out of service.
-
-
-
-
-Kantor & Lapsley [Page 1]
-
-
-
-RFC 977 February 1986
-Network News Transfer Protocol
-
-
-1.2. The USENET News System
-
- Clearly, a worthwhile reduction of the amount of these resources used
- can be achieved if articles are stored in a central database on the
- receiving host instead of in each subscriber's mailbox. The USENET
- news system provides a method of doing just this. There is a central
- repository of the news articles in one place (customarily a spool
- directory of some sort), and a set of programs that allow a
- subscriber to select those items he wishes to read. Indexing,
- cross-referencing, and expiration of aged messages are also provided.
-
-1.3. Central Storage of News
-
- For clusters of hosts connected together by fast local area networks
- (such as Ethernet), it makes even more sense to consolidate news
- distribution onto one (or a very few) hosts, and to allow access to
- these news articles using a server and client model. Subscribers may
- then request only the articles they wish to see, without having to
- wastefully duplicate the storage of a copy of each item on each host.
-
-1.4. A Central News Server
-
- A way to achieve these economies is to have a central computer system
- that can provide news service to the other systems on the local area
- network. Such a server would manage the collection of news articles
- and index files, with each person who desires to read news bulletins
- doing so over the LAN. For a large cluster of computer systems, the
- savings in total disk space is clearly worthwhile. Also, this allows
- workstations with limited disk storage space to participate in the
- news without incoming items consuming oppressive amounts of the
- workstation's disk storage.
-
- We have heard rumors of somewhat successful attempts to provide
- centralized news service using IBIS and other shared or distributed
- file systems. While it is possible that such a distributed file
- system implementation might work well with a group of similar
- computers running nearly identical operating systems, such a scheme
- is not general enough to offer service to a wide range of client
- systems, especially when many diverse operating systems may be in use
- among a group of clients. There are few (if any) shared or networked
- file systems that can offer the generality of service that stream
- connections using Internet TCP provide, particularly when a wide
- range of host hardware and operating systems are considered.
-
- NNTP specifies a protocol for the distribution, inquiry, retrieval,
- and posting of news articles using a reliable stream (such as TCP)
- server-client model. NNTP is designed so that news articles need only
-
-
-Kantor & Lapsley [Page 2]
-
-
-
-RFC 977 February 1986
-Network News Transfer Protocol
-
-
- be stored on one (presumably central) host, and subscribers on other
- hosts attached to the LAN may read news articles using stream
- connections to the news host.
-
- NNTP is modelled upon the news article specifications in RFC 850,
- which describes the USENET news system. However, NNTP makes few
- demands upon the structure, content, or storage of news articles, and
- thus we believe it easily can be adapted to other non-USENET news
- systems.
-
- Typically, the NNTP server runs as a background process on one host,
- and would accept connections from other hosts on the LAN. This works
- well when there are a number of small computer systems (such as
- workstations, with only one or at most a few users each), and a large
- central server.
-
-1.5. Intermediate News Servers
-
- For clusters of machines with many users (as might be the case in a
- university or large industrial environment), an intermediate server
- might be used. This intermediate or "slave" server runs on each
- computer system, and is responsible for mediating news reading
- requests and performing local caching of recently-retrieved news
- articles.
-
- Typically, a client attempting to obtain news service would first
- attempt to connect to the news service port on the local machine. If
- this attempt were unsuccessful, indicating a failed server, an
- installation might choose to either deny news access, or to permit
- connection to the central "master" news server.
-
- For workstations or other small systems, direct connection to the
- master server would probably be the normal manner of operation.
-
- This specification does not cover the operation of slave NNTP
- servers. We merely suggest that slave servers are a logical addition
- to NNTP server usage which would enhance operation on large local
- area networks.
-
-1.6. News Distribution
-
- NNTP has commands which provide a straightforward method of
- exchanging articles between cooperating hosts. Hosts which are well
- connected on a local area or other fast network and who wish to
- actually obtain copies of news articles for local storage might well
- find NNTP to be a more efficient way to distribute news than more
- traditional transfer methods (such as UUCP).
-
-
-Kantor & Lapsley [Page 3]
-
-
-
-RFC 977 February 1986
-Network News Transfer Protocol
-
-
- In the traditional method of distributing news articles, news is
- propagated from host to host by flooding - that is, each host will
- send all its new news articles on to each host that it feeds. These
- hosts will then in turn send these new articles on to other hosts
- that they feed. Clearly, sending articles that a host already has
- obtained a copy of from another feed (many hosts that receive news
- are redundantly fed) again is a waste of time and communications
- resources, but for transport mechanisms that are single-transaction
- based rather than interactive (such as UUCP in the UNIX-world <1>),
- distribution time is diminished by sending all articles and having
- the receiving host simply discard the duplicates. This is an
- especially true when communications sessions are limited to once a
- day.
-
- Using NNTP, hosts exchanging news articles have an interactive
- mechanism for deciding which articles are to be transmitted. A host
- desiring new news, or which has new news to send, will typically
- contact one or more of its neighbors using NNTP. First it will
- inquire if any new news groups have been created on the serving host
- by means of the NEWGROUPS command. If so, and those are appropriate
- or desired (as established by local site-dependent rules), those new
- newsgroups can be created.
-
- The client host will then inquire as to which new articles have
- arrived in all or some of the newsgroups that it desires to receive,
- using the NEWNEWS command. It will receive a list of new articles
- from the server, and can request transmission of those articles that
- it desires and does not already have.
-
- Finally, the client can advise the server of those new articles which
- the client has recently received. The server will indicate those
- articles that it has already obtained copies of, and which articles
- should be sent to add to its collection.
-
- In this manner, only those articles which are not duplicates and
- which are desired are transferred.
-
-
-
-
-
-
-
-
-
-
-
-
-
-Kantor & Lapsley [Page 4]
-
-
-
-RFC 977 February 1986
-Network News Transfer Protocol
-
-
-2. The NNTP Specification
-
-2.1. Overview
-
- The news server specified by this document uses a stream connection
- (such as TCP) and SMTP-like commands and responses. It is designed
- to accept connections from hosts, and to provide a simple interface
- to the news database.
-
- This server is only an interface between programs and the news
- databases. It does not perform any user interaction or presentation-
- level functions. These "user-friendly" functions are better left to
- the client programs, which have a better understanding of the
- environment in which they are operating.
-
- When used via Internet TCP, the contact port assigned for this
- service is 119.
-
-2.2. Character Codes
-
- Commands and replies are composed of characters from the ASCII
- character set. When the transport service provides an 8-bit byte
- (octet) transmission channel, each 7-bit character is transmitted
- right justified in an octet with the high order bit cleared to zero.
-
-2.3. Commands
-
- Commands consist of a command word, which in some cases may be
- followed by a parameter. Commands with parameters must separate the
- parameters from each other and from the command by one or more space
- or tab characters. Command lines must be complete with all required
- parameters, and may not contain more than one command.
-
- Commands and command parameters are not case sensitive. That is, a
- command or parameter word may be upper case, lower case, or any
- mixture of upper and lower case.
-
- Each command line must be terminated by a CR-LF (Carriage Return -
- Line Feed) pair.
-
- Command lines shall not exceed 512 characters in length, counting all
- characters including spaces, separators, punctuation, and the
- trailing CR-LF (thus there are 510 characters maximum allowed for the
- command and its parameters). There is no provision for continuation
- command lines.
-
-
-
-
-Kantor & Lapsley [Page 5]
-
-
-
-RFC 977 February 1986
-Network News Transfer Protocol
-
-
-2.4. Responses
-
- Responses are of two kinds, textual and status.
-
-2.4.1. Text Responses
-
- Text is sent only after a numeric status response line has been sent
- that indicates that text will follow. Text is sent as a series of
- successive lines of textual matter, each terminated with CR-LF pair.
- A single line containing only a period (.) is sent to indicate the
- end of the text (i.e., the server will send a CR-LF pair at the end
- of the last line of text, a period, and another CR-LF pair).
-
- If the text contained a period as the first character of the text
- line in the original, that first period is doubled. Therefore, the
- client must examine the first character of each line received, and
- for those beginning with a period, determine either that this is the
- end of the text or whether to collapse the doubled period to a single
- one.
-
- The intention is that text messages will usually be displayed on the
- user's terminal whereas command/status responses will be interpreted
- by the client program before any possible display is done.
-
-2.4.2. Status Responses
-
- These are status reports from the server and indicate the response to
- the last command received from the client.
-
- Status response lines begin with a 3 digit numeric code which is
- sufficient to distinguish all responses. Some of these may herald
- the subsequent transmission of text.
-
- The first digit of the response broadly indicates the success,
- failure, or progress of the previous command.
-
- 1xx - Informative message
- 2xx - Command ok
- 3xx - Command ok so far, send the rest of it.
- 4xx - Command was correct, but couldn't be performed for
- some reason.
- 5xx - Command unimplemented, or incorrect, or a serious
- program error occurred.
-
-
-
-
-
-
-Kantor & Lapsley [Page 6]
-
-
-
-RFC 977 February 1986
-Network News Transfer Protocol
-
-
- The next digit in the code indicates the function response category.
-
- x0x - Connection, setup, and miscellaneous messages
- x1x - Newsgroup selection
- x2x - Article selection
- x3x - Distribution functions
- x4x - Posting
- x8x - Nonstandard (private implementation) extensions
- x9x - Debugging output
-
- The exact response codes that should be expected from each command
- are detailed in the description of that command. In addition, below
- is listed a general set of response codes that may be received at any
- time.
-
- Certain status responses contain parameters such as numbers and
- names. The number and type of such parameters is fixed for each
- response code to simplify interpretation of the response.
-
- Parameters are separated from the numeric response code and from each
- other by a single space. All numeric parameters are decimal, and may
- have leading zeros. All string parameters begin after the separating
- space, and end before the following separating space or the CR-LF
- pair at the end of the line. (String parameters may not, therefore,
- contain spaces.) All text, if any, in the response which is not a
- parameter of the response must follow and be separated from the last
- parameter by a space. Also, note that the text following a response
- number may vary in different implementations of the server. The
- 3-digit numeric code should be used to determine what response was
- sent.
-
- Response codes not specified in this standard may be used for any
- installation-specific additional commands also not specified. These
- should be chosen to fit the pattern of x8x specified above. (Note
- that debugging is provided for explicitly in the x9x response codes.)
- The use of unspecified response codes for standard commands is
- prohibited.
-
- We have provided a response pattern x9x for debugging. Since much
- debugging output may be classed as "informative messages", we would
- expect, therefore, that responses 190 through 199 would be used for
- various debugging outputs. There is no requirement in this
- specification for debugging output, but if such is provided over the
- connected stream, it must use these response codes. If appropriate
- to a specific implementation, other x9x codes may be used for
- debugging. (An example might be to use e.g., 290 to acknowledge a
- remote debugging request.)
-
-
-Kantor & Lapsley [Page 7]
-
-
-
-RFC 977 February 1986
-Network News Transfer Protocol
-
-
-2.4.3. General Responses
-
- The following is a list of general response codes that may be sent by
- the NNTP server. These are not specific to any one command, but may
- be returned as the result of a connection, a failure, or some unusual
- condition.
-
- In general, 1xx codes may be ignored or displayed as desired; code
- 200 or 201 is sent upon initial connection to the NNTP server
- depending upon posting permission; code 400 will be sent when the
- NNTP server discontinues service (by operator request, for example);
- and 5xx codes indicate that the command could not be performed for
- some unusual reason.
-
- 100 help text
- 190
- through
- 199 debug output
-
- 200 server ready - posting allowed
- 201 server ready - no posting allowed
-
- 400 service discontinued
-
- 500 command not recognized
- 501 command syntax error
- 502 access restriction or permission denied
- 503 program fault - command not performed
-
-3. Command and Response Details
-
- On the following pages are descriptions of each command recognized by
- the NNTP server and the responses which will be returned by those
- commands.
-
- Each command is shown in upper case for clarity, although case is
- ignored in the interpretation of commands by the NNTP server. Any
- parameters are shown in lower case. A parameter shown in [square
- brackets] is optional. For example, [GMT] indicates that the
- triglyph GMT may present or omitted.
-
- Every command described in this section must be implemented by all
- NNTP servers.
-
-
-
-
-
-
-Kantor & Lapsley [Page 8]
-
-
-
-RFC 977 February 1986
-Network News Transfer Protocol
-
-
- There is no prohibition against additional commands being added;
- however, it is recommended that any such unspecified command begin
- with the letter "X" to avoid conflict with later revisions of this
- specification.
-
- Implementors are reminded that such additional commands may not
- redefine specified status response codes. Using additional
- unspecified responses for standard commands is also prohibited.
-
-3.1. The ARTICLE, BODY, HEAD, and STAT commands
-
- There are two forms to the ARTICLE command (and the related BODY,
- HEAD, and STAT commands), each using a different method of specifying
- which article is to be retrieved. When the ARTICLE command is
- followed by a message-id in angle brackets ("<" and ">"), the first
- form of the command is used; when a numeric parameter or no parameter
- is supplied, the second form is invoked.
-
- The text of the article is returned as a textual response, as
- described earlier in this document.
-
- The HEAD and BODY commands are identical to the ARTICLE command
- except that they respectively return only the header lines or text
- body of the article.
-
- The STAT command is similar to the ARTICLE command except that no
- text is returned. When selecting by message number within a group,
- the STAT command serves to set the current article pointer without
- sending text. The returned acknowledgement response will contain the
- message-id, which may be of some value. Using the STAT command to
- select by message-id is valid but of questionable value, since a
- selection by message-id does NOT alter the "current article pointer".
-
-3.1.1. ARTICLE (selection by message-id)
-
- ARTICLE <message-id>
-
- Display the header, a blank line, then the body (text) of the
- specified article. Message-id is the message id of an article as
- shown in that article's header. It is anticipated that the client
- will obtain the message-id from a list provided by the NEWNEWS
- command, from references contained within another article, or from
- the message-id provided in the response to some other commands.
-
- Please note that the internally-maintained "current article pointer"
- is NOT ALTERED by this command. This is both to facilitate the
- presentation of articles that may be referenced within an article
-
-
-Kantor & Lapsley [Page 9]
-
-
-
-RFC 977 February 1986
-Network News Transfer Protocol
-
-
- being read, and because of the semantic difficulties of determining
- the proper sequence and membership of an article which may have been
- posted to more than one newsgroup.
-
-3.1.2. ARTICLE (selection by number)
-
- ARTICLE [nnn]
-
- Displays the header, a blank line, then the body (text) of the
- current or specified article. The optional parameter nnn is the
-
- numeric id of an article in the current newsgroup and must be chosen
- from the range of articles provided when the newsgroup was selected.
- If it is omitted, the current article is assumed.
-
- The internally-maintained "current article pointer" is set by this
- command if a valid article number is specified.
-
- [the following applies to both forms of the article command.] A
- response indicating the current article number, a message-id string,
- and that text is to follow will be returned.
-
- The message-id string returned is an identification string contained
- within angle brackets ("<" and ">"), which is derived from the header
- of the article itself. The Message-ID header line (required by
- RFC850) from the article must be used to supply this information. If
- the message-id header line is missing from the article, a single
- digit "0" (zero) should be supplied within the angle brackets.
-
- Since the message-id field is unique with each article, it may be
- used by a news reading program to skip duplicate displays of articles
- that have been posted more than once, or to more than one newsgroup.
-
-3.1.3. Responses
-
- 220 n <a> article retrieved - head and body follow
- (n = article number, <a> = message-id)
- 221 n <a> article retrieved - head follows
- 222 n <a> article retrieved - body follows
- 223 n <a> article retrieved - request text separately
- 412 no newsgroup has been selected
- 420 no current article has been selected
- 423 no such article number in this group
- 430 no such article found
-
-
-
-
-
-Kantor & Lapsley [Page 10]
-
-
-
-RFC 977 February 1986
-Network News Transfer Protocol
-
-
-3.2. The GROUP command
-
-3.2.1. GROUP
-
- GROUP ggg
-
- The required parameter ggg is the name of the newsgroup to be
- selected (e.g. "net.news"). A list of valid newsgroups may be
- obtained from the LIST command.
-
- The successful selection response will return the article numbers of
- the first and last articles in the group, and an estimate of the
- number of articles on file in the group. It is not necessary that
- the estimate be correct, although that is helpful; it must only be
- equal to or larger than the actual number of articles on file. (Some
- implementations will actually count the number of articles on file.
- Others will just subtract first article number from last to get an
- estimate.)
-
- When a valid group is selected by means of this command, the
- internally maintained "current article pointer" is set to the first
- article in the group. If an invalid group is specified, the
- previously selected group and article remain selected. If an empty
- newsgroup is selected, the "current article pointer" is in an
- indeterminate state and should not be used.
-
- Note that the name of the newsgroup is not case-dependent. It must
- otherwise match a newsgroup obtained from the LIST command or an
- error will result.
-
-3.2.2. Responses
-
- 211 n f l s group selected
- (n = estimated number of articles in group,
- f = first article number in the group,
- l = last article number in the group,
- s = name of the group.)
- 411 no such news group
-
-
-
-
-
-
-
-
-
-
-
-Kantor & Lapsley [Page 11]
-
-
-
-RFC 977 February 1986
-Network News Transfer Protocol
-
-
-3.3. The HELP command
-
-3.3.1. HELP
-
- HELP
-
- Provides a short summary of commands that are understood by this
- implementation of the server. The help text will be presented as a
- textual response, terminated by a single period on a line by itself.
-
- 3.3.2. Responses
-
- 100 help text follows
-
-3.4. The IHAVE command
-
-3.4.1. IHAVE
-
- IHAVE <messageid>
-
- The IHAVE command informs the server that the client has an article
- whose id is <messageid>. If the server desires a copy of that
- article, it will return a response instructing the client to send the
- entire article. If the server does not want the article (if, for
- example, the server already has a copy of it), a response indicating
- that the article is not wanted will be returned.
-
- If transmission of the article is requested, the client should send
- the entire article, including header and body, in the manner
- specified for text transmission from the server. A response code
- indicating success or failure of the transferral of the article will
- be returned.
-
- This function differs from the POST command in that it is intended
- for use in transferring already-posted articles between hosts.
- Normally it will not be used when the client is a personal
- newsreading program. In particular, this function will invoke the
- server's news posting program with the appropriate settings (flags,
- options, etc) to indicate that the forthcoming article is being
- forwarded from another host.
-
- The server may, however, elect not to post or forward the article if
- after further examination of the article it deems it inappropriate to
- do so. The 436 or 437 error codes may be returned as appropriate to
- the situation.
-
- Reasons for such subsequent rejection of an article may include such
-
-
-Kantor & Lapsley [Page 12]
-
-
-
-RFC 977 February 1986
-Network News Transfer Protocol
-
-
- problems as inappropriate newsgroups or distributions, disk space
- limitations, article lengths, garbled headers, and the like. These
- are typically restrictions enforced by the server host's news
- software and not necessarily the NNTP server itself.
-
-3.4.2. Responses
-
- 235 article transferred ok
- 335 send article to be transferred. End with <CR-LF>.<CR-LF>
- 435 article not wanted - do not send it
- 436 transfer failed - try again later
- 437 article rejected - do not try again
-
- An implementation note:
-
- Because some host news posting software may not be able to decide
- immediately that an article is inappropriate for posting or
- forwarding, it is acceptable to acknowledge the successful transfer
- of the article and to later silently discard it. Thus it is
- permitted to return the 235 acknowledgement code and later discard
- the received article. This is not a fully satisfactory solution to
- the problem. Perhaps some implementations will wish to send mail to
- the author of the article in certain of these cases.
-
-3.5. The LAST command
-
-3.5.1. LAST
-
- LAST
-
- The internally maintained "current article pointer" is set to the
- previous article in the current newsgroup. If already positioned at
- the first article of the newsgroup, an error message is returned and
- the current article remains selected.
-
- The internally-maintained "current article pointer" is set by this
- command.
-
- A response indicating the current article number, and a message-id
- string will be returned. No text is sent in response to this
- command.
-
-3.5.2. Responses
-
- 223 n a article retrieved - request text separately
- (n = article number, a = unique article id)
-
-
-
-Kantor & Lapsley [Page 13]
-
-
-
-RFC 977 February 1986
-Network News Transfer Protocol
-
-
- 412 no newsgroup selected
- 420 no current article has been selected
- 422 no previous article in this group
-
-3.6. The LIST command
-
-3.6.1. LIST
-
- LIST
-
- Returns a list of valid newsgroups and associated information. Each
- newsgroup is sent as a line of text in the following format:
-
- group last first p
-
- where <group> is the name of the newsgroup, <last> is the number of
- the last known article currently in that newsgroup, <first> is the
- number of the first article currently in the newsgroup, and <p> is
- either 'y' or 'n' indicating whether posting to this newsgroup is
- allowed ('y') or prohibited ('n').
-
- The <first> and <last> fields will always be numeric. They may have
- leading zeros. If the <last> field evaluates to less than the
- <first> field, there are no articles currently on file in the
- newsgroup.
-
- Note that posting may still be prohibited to a client even though the
- LIST command indicates that posting is permitted to a particular
- newsgroup. See the POST command for an explanation of client
- prohibitions. The posting flag exists for each newsgroup because
- some newsgroups are moderated or are digests, and therefore cannot be
- posted to; that is, articles posted to them must be mailed to a
- moderator who will post them for the submitter. This is independent
- of the posting permission granted to a client by the NNTP server.
-
- Please note that an empty list (i.e., the text body returned by this
- command consists only of the terminating period) is a possible valid
- response, and indicates that there are currently no valid newsgroups.
-
-3.6.2. Responses
-
- 215 list of newsgroups follows
-
-
-
-
-
-
-
-Kantor & Lapsley [Page 14]
-
-
-
-RFC 977 February 1986
-Network News Transfer Protocol
-
-
-3.7. The NEWGROUPS command
-
-3.7.1. NEWGROUPS
-
- NEWGROUPS date time [GMT] [<distributions>]
-
- A list of newsgroups created since <date and time> will be listed in
- the same format as the LIST command.
-
- The date is sent as 6 digits in the format YYMMDD, where YY is the
- last two digits of the year, MM is the two digits of the month (with
- leading zero, if appropriate), and DD is the day of the month (with
- leading zero, if appropriate). The closest century is assumed as
- part of the year (i.e., 86 specifies 1986, 30 specifies 2030, 99 is
- 1999, 00 is 2000).
-
- Time must also be specified. It must be as 6 digits HHMMSS with HH
- being hours on the 24-hour clock, MM minutes 00-59, and SS seconds
- 00-59. The time is assumed to be in the server's timezone unless the
- token "GMT" appears, in which case both time and date are evaluated
- at the 0 meridian.
-
- The optional parameter "distributions" is a list of distribution
- groups, enclosed in angle brackets. If specified, the distribution
- portion of a new newsgroup (e.g, 'net' in 'net.wombat') will be
- examined for a match with the distribution categories listed, and
- only those new newsgroups which match will be listed. If more than
- one distribution group is to be listed, they must be separated by
- commas within the angle brackets.
-
- Please note that an empty list (i.e., the text body returned by this
- command consists only of the terminating period) is a possible valid
- response, and indicates that there are currently no new newsgroups.
-
-3.7.2. Responses
-
- 231 list of new newsgroups follows
-
-
-
-
-
-
-
-
-
-
-
-
-Kantor & Lapsley [Page 15]
-
-
-
-RFC 977 February 1986
-Network News Transfer Protocol
-
-
-3.8. The NEWNEWS command
-
-3.8.1. NEWNEWS
-
- NEWNEWS newsgroups date time [GMT] [<distribution>]
-
- A list of message-ids of articles posted or received to the specified
- newsgroup since "date" will be listed. The format of the listing will
- be one message-id per line, as though text were being sent. A single
- line consisting solely of one period followed by CR-LF will terminate
- the list.
-
- Date and time are in the same format as the NEWGROUPS command.
-
- A newsgroup name containing a "*" (an asterisk) may be specified to
- broaden the article search to some or all newsgroups. The asterisk
- will be extended to match any part of a newsgroup name (e.g.,
- net.micro* will match net.micro.wombat, net.micro.apple, etc). Thus
- if only an asterisk is given as the newsgroup name, all newsgroups
- will be searched for new news.
-
- (Please note that the asterisk "*" expansion is a general
- replacement; in particular, the specification of e.g., net.*.unix
- should be correctly expanded to embrace names such as net.wombat.unix
- and net.whocares.unix.)
-
- Conversely, if no asterisk appears in a given newsgroup name, only
- the specified newsgroup will be searched for new articles. Newsgroup
- names must be chosen from those returned in the listing of available
- groups. Multiple newsgroup names (including a "*") may be specified
- in this command, separated by a comma. No comma shall appear after
- the last newsgroup in the list. [Implementors are cautioned to keep
- the 512 character command length limit in mind.]
-
- The exclamation point ("!") may be used to negate a match. This can
- be used to selectively omit certain newsgroups from an otherwise
- larger list. For example, a newsgroups specification of
- "net.*,mod.*,!mod.map.*" would specify that all net.<anything> and
- all mod.<anything> EXCEPT mod.map.<anything> newsgroup names would be
- matched. If used, the exclamation point must appear as the first
- character of the given newsgroup name or pattern.
-
- The optional parameter "distributions" is a list of distribution
- groups, enclosed in angle brackets. If specified, the distribution
- portion of an article's newsgroup (e.g, 'net' in 'net.wombat') will
- be examined for a match with the distribution categories listed, and
- only those articles which have at least one newsgroup belonging to
-
-
-Kantor & Lapsley [Page 16]
-
-
-
-RFC 977 February 1986
-Network News Transfer Protocol
-
-
- the list of distributions will be listed. If more than one
- distribution group is to be supplied, they must be separated by
- commas within the angle brackets.
-
- The use of the IHAVE, NEWNEWS, and NEWGROUPS commands to distribute
- news is discussed in an earlier part of this document.
-
- Please note that an empty list (i.e., the text body returned by this
- command consists only of the terminating period) is a possible valid
- response, and indicates that there is currently no new news.
-
-3.8.2. Responses
-
- 230 list of new articles by message-id follows
-
-3.9. The NEXT command
-
-3.9.1. NEXT
-
- NEXT
-
- The internally maintained "current article pointer" is advanced to
- the next article in the current newsgroup. If no more articles
- remain in the current group, an error message is returned and the
- current article remains selected.
-
- The internally-maintained "current article pointer" is set by this
- command.
-
- A response indicating the current article number, and the message-id
- string will be returned. No text is sent in response to this
- command.
-
-3.9.2. Responses
-
- 223 n a article retrieved - request text separately
- (n = article number, a = unique article id)
- 412 no newsgroup selected
- 420 no current article has been selected
- 421 no next article in this group
-
-
-
-
-
-
-
-
-
-Kantor & Lapsley [Page 17]
-
-
-
-RFC 977 February 1986
-Network News Transfer Protocol
-
-
-3.10. The POST command
-
-3.10.1. POST
-
- POST
-
- If posting is allowed, response code 340 is returned to indicate that
- the article to be posted should be sent. Response code 440 indicates
- that posting is prohibited for some installation-dependent reason.
-
- If posting is permitted, the article should be presented in the
- format specified by RFC850, and should include all required header
- lines. After the article's header and body have been completely sent
- by the client to the server, a further response code will be returned
- to indicate success or failure of the posting attempt.
-
- The text forming the header and body of the message to be posted
- should be sent by the client using the conventions for text received
- from the news server: A single period (".") on a line indicates the
- end of the text, with lines starting with a period in the original
- text having that period doubled during transmission.
-
- No attempt shall be made by the server to filter characters, fold or
- limit lines, or otherwise process incoming text. It is our intent
- that the server just pass the incoming message to be posted to the
- server installation's news posting software, which is separate from
- this specification. See RFC850 for more details.
-
- Since most installations will want the client news program to allow
- the user to prepare his message using some sort of text editor, and
- transmit it to the server for posting only after it is composed, the
- client program should take note of the herald message that greeted it
- when the connection was first established. This message indicates
- whether postings from that client are permitted or not, and can be
- used to caution the user that his access is read-only if that is the
- case. This will prevent the user from wasting a good deal of time
- composing a message only to find posting of the message was denied.
- The method and determination of which clients and hosts may post is
- installation dependent and is not covered by this specification.
-
-3.10.2. Responses
-
- 240 article posted ok
- 340 send article to be posted. End with <CR-LF>.<CR-LF>
- 440 posting not allowed
- 441 posting failed
-
-
-
-Kantor & Lapsley [Page 18]
-
-
-
-RFC 977 February 1986
-Network News Transfer Protocol
-
-
- (for reference, one of the following codes will be sent upon initial
- connection; the client program should determine whether posting is
- generally permitted from these:) 200 server ready - posting allowed
- 201 server ready - no posting allowed
-
-3.11. The QUIT command
-
-3.11.1. QUIT
-
- QUIT
-
- The server process acknowledges the QUIT command and then closes the
- connection to the client. This is the preferred method for a client
- to indicate that it has finished all its transactions with the NNTP
- server.
-
- If a client simply disconnects (or the connection times out, or some
- other fault occurs), the server should gracefully cease its attempts
- to service the client.
-
-3.11.2. Responses
-
- 205 closing connection - goodbye!
-
-3.12. The SLAVE command
-
-3.12.1. SLAVE
-
- SLAVE
-
- Indicates to the server that this client connection is to a slave
- server, rather than a user.
-
- This command is intended for use in separating connections to single
- users from those to subsidiary ("slave") servers. It may be used to
- indicate that priority should therefore be given to requests from
- this client, as it is presumably serving more than one person. It
- might also be used to determine which connections to close when
- system load levels are exceeded, perhaps giving preference to slave
- servers. The actual use this command is put to is entirely
- implementation dependent, and may vary from one host to another. In
- NNTP servers which do not give priority to slave servers, this
- command must nonetheless be recognized and acknowledged.
-
-3.12.2. Responses
-
- 202 slave status noted
-
-
-Kantor & Lapsley [Page 19]
-
-
-
-RFC 977 February 1986
-Network News Transfer Protocol
-
-
-4. Sample Conversations
-
- These are samples of the conversations that might be expected with
- the news server in hypothetical sessions. The notation C: indicates
- commands sent to the news server from the client program; S: indicate
- responses received from the server by the client.
-
-4.1. Example 1 - relative access with NEXT
-
- S: (listens at TCP port 119)
-
- C: (requests connection on TCP port 119)
- S: 200 wombatvax news server ready - posting ok
-
- (client asks for a current newsgroup list)
- C: LIST
- S: 215 list of newsgroups follows
- S: net.wombats 00543 00501 y
- S: net.unix-wizards 10125 10011 y
- (more information here)
- S: net.idiots 00100 00001 n
- S: .
-
- (client selects a newsgroup)
- C: GROUP net.unix-wizards
- S: 211 104 10011 10125 net.unix-wizards group selected
- (there are 104 articles on file, from 10011 to 10125)
-
- (client selects an article to read)
- C: STAT 10110
- S: 223 10110 <23445@sdcsvax.ARPA> article retrieved - statistics
- only (article 10110 selected, its message-id is
- <23445@sdcsvax.ARPA>)
-
- (client examines the header)
- C: HEAD
- S: 221 10110 <23445@sdcsvax.ARPA> article retrieved - head
- follows (text of the header appears here)
- S: .
-
- (client wants to see the text body of the article)
- C: BODY
- S: 222 10110 <23445@sdcsvax.ARPA> article retrieved - body
- follows (body text here)
- S: .
-
- (client selects next article in group)
-
-
-Kantor & Lapsley [Page 20]
-
-
-
-RFC 977 February 1986
-Network News Transfer Protocol
-
-
- C: NEXT
- S: 223 10113 <21495@nudebch.uucp> article retrieved - statistics
- only (article 10113 was next in group)
-
- (client finishes session)
- C: QUIT
- S: 205 goodbye.
-
-4.2. Example 2 - absolute article access with ARTICLE
-
- S: (listens at TCP port 119)
-
- C: (requests connection on TCP port 119)
- S: 201 UCB-VAX netnews server ready -- no posting allowed
-
- C: GROUP msgs
- S: 211 103 402 504 msgs Your new group is msgs
- (there are 103 articles, from 402 to 504)
-
- C: ARTICLE 401
- S: 423 No such article in this newsgroup
-
- C: ARTICLE 402
- S: 220 402 <4105@ucbvax.ARPA> Article retrieved, text follows
- S: (article header and body follow)
- S: .
-
- C: HEAD 403
- S: 221 403 <3108@mcvax.UUCP> Article retrieved, header follows
- S: (article header follows)
- S: .
-
- C: QUIT
- S: 205 UCB-VAX news server closing connection. Goodbye.
-
-4.3. Example 3 - NEWGROUPS command
-
- S: (listens at TCP port 119)
-
- C: (requests connection on TCP port 119)
- S: 200 Imaginary Institute News Server ready (posting ok)
-
- (client asks for new newsgroups since April 3, 1985)
- C: NEWGROUPS 850403 020000
-
- S: 231 New newsgroups since 03/04/85 02:00:00 follow
-
-
-
-Kantor & Lapsley [Page 21]
-
-
-
-RFC 977 February 1986
-Network News Transfer Protocol
-
-
- S: net.music.gdead
- S: net.games.sources
- S: .
-
- C: GROUP net.music.gdead
- S: 211 0 1 1 net.music.gdead Newsgroup selected
- (there are no articles in that newsgroup, and
- the first and last article numbers should be ignored)
-
- C: QUIT
- S: 205 Imaginary Institute news server ceasing service. Bye!
-
-4.4. Example 4 - posting a news article
-
- S: (listens at TCP port 119)
-
- C: (requests connection on TCP port 119)
- S: 200 BANZAIVAX news server ready, posting allowed.
-
- C: POST
- S: 340 Continue posting; Period on a line by itself to end
- C: (transmits news article in RFC850 format)
- C: .
- S: 240 Article posted successfully.
-
- C: QUIT
- S: 205 BANZAIVAX closing connection. Goodbye.
-
-4.5. Example 5 - interruption due to operator request
-
- S: (listens at TCP port 119)
-
- C: (requests connection on TCP port 119)
- S: 201 genericvax news server ready, no posting allowed.
-
- (assume normal conversation for some time, and
- that a newsgroup has been selected)
-
- C: NEXT
- S: 223 1013 <5734@mcvax.UUCP> Article retrieved; text separate.
-
- C: HEAD
- C: 221 1013 <5734@mcvax.UUCP> Article retrieved; head follows.
-
- S: (sends head of article, but halfway through is
- interrupted by an operator request. The following
- then occurs, without client intervention.)
-
-
-Kantor & Lapsley [Page 22]
-
-
-
-RFC 977 February 1986
-Network News Transfer Protocol
-
-
- S: (ends current line with a CR-LF pair)
- S: .
- S: 400 Connection closed by operator. Goodbye.
- S: (closes connection)
-
-4.6. Example 6 - Using the news server to distribute news between
- systems.
-
- S: (listens at TCP port 119)
-
- C: (requests connection on TCP port 119)
- S: 201 Foobar NNTP server ready (no posting)
-
- (client asks for new newsgroups since 2 am, May 15, 1985)
- C: NEWGROUPS 850515 020000
- S: 235 New newsgroups since 850515 follow
- S: net.fluff
- S: net.lint
- S: .
-
- (client asks for new news articles since 2 am, May 15, 1985)
- C: NEWNEWS * 850515 020000
- S: 230 New news since 850515 020000 follows
- S: <1772@foo.UUCP>
- S: <87623@baz.UUCP>
- S: <17872@GOLD.CSNET>
- S: .
-
- (client asks for article <1772@foo.UUCP>)
- C: ARTICLE <1772@foo.UUCP>
- S: 220 <1772@foo.UUCP> All of article follows
- S: (sends entire message)
- S: .
-
- (client asks for article <87623@baz.UUCP>
- C: ARTICLE <87623@baz.UUCP>
- S: 220 <87623@baz.UUCP> All of article follows
- S: (sends entire message)
- S: .
-
- (client asks for article <17872@GOLD.CSNET>
- C: ARTICLE <17872@GOLD.CSNET>
- S: 220 <17872@GOLD.CSNET> All of article follows
- S: (sends entire message)
- S: .
-
-
-
-
-Kantor & Lapsley [Page 23]
-
-
-
-RFC 977 February 1986
-Network News Transfer Protocol
-
-
- (client offers an article it has received recently)
- C: IHAVE <4105@ucbvax.ARPA>
- S: 435 Already seen that one, where you been?
-
- (client offers another article)
- C: IHAVE <4106@ucbvax.ARPA>
- S: 335 News to me! <CRLF.CRLF> to end.
- C: (sends article)
- C: .
- S: 235 Article transferred successfully. Thanks.
-
- (or)
-
- S: 436 Transfer failed.
-
- (client is all through with the session)
- C: QUIT
- S: 205 Foobar NNTP server bids you farewell.
-
-4.7. Summary of commands and responses.
-
- The following are the commands recognized and responses returned by
- the NNTP server.
-
-4.7.1. Commands
-
- ARTICLE
- BODY
- GROUP
- HEAD
- HELP
- IHAVE
- LAST
- LIST
- NEWGROUPS
- NEWNEWS
- NEXT
- POST
- QUIT
- SLAVE
- STAT
-
-4.7.2. Responses
-
- 100 help text follows
- 199 debug output
-
-
-
-Kantor & Lapsley [Page 24]
-
-
-
-RFC 977 February 1986
-Network News Transfer Protocol
-
-
- 200 server ready - posting allowed
- 201 server ready - no posting allowed
- 202 slave status noted
- 205 closing connection - goodbye!
- 211 n f l s group selected
- 215 list of newsgroups follows
- 220 n <a> article retrieved - head and body follow 221 n <a> article
- retrieved - head follows
- 222 n <a> article retrieved - body follows
- 223 n <a> article retrieved - request text separately 230 list of new
- articles by message-id follows
- 231 list of new newsgroups follows
- 235 article transferred ok
- 240 article posted ok
-
- 335 send article to be transferred. End with <CR-LF>.<CR-LF>
- 340 send article to be posted. End with <CR-LF>.<CR-LF>
-
- 400 service discontinued
- 411 no such news group
- 412 no newsgroup has been selected
- 420 no current article has been selected
- 421 no next article in this group
- 422 no previous article in this group
- 423 no such article number in this group
- 430 no such article found
- 435 article not wanted - do not send it
- 436 transfer failed - try again later
- 437 article rejected - do not try again.
- 440 posting not allowed
- 441 posting failed
-
- 500 command not recognized
- 501 command syntax error
- 502 access restriction or permission denied
- 503 program fault - command not performed
-
-4.8. A Brief Word about the USENET News System
-
- In the UNIX world, which traditionally has been linked by 1200 baud
- dial-up telephone lines, the USENET News system has evolved to handle
- central storage, indexing, retrieval, and distribution of news. With
- the exception of its underlying transport mechanism (UUCP), USENET
- News is an efficient means of providing news and bulletin service to
- subscribers on UNIX and other hosts worldwide. The USENET News
-
-
-
-
-Kantor & Lapsley [Page 25]
-
-
-
-RFC 977 February 1986
-Network News Transfer Protocol
-
-
- system is discussed in detail in RFC 850. It runs on most versions
- of UNIX and on many other operating systems, and is customarily
- distributed without charge.
-
- USENET uses a spooling area on the UNIX host to store news articles,
- one per file. Each article consists of a series of heading text,
- which contain the sender's identification and organizational
- affiliation, timestamps, electronic mail reply paths, subject,
- newsgroup (subject category), and the like. A complete news article
- is reproduced in its entirety below. Please consult RFC 850 for more
- details.
-
- Relay-Version: version B 2.10.3 4.3bsd-beta 6/6/85; site
- sdcsvax.UUCP
- Posting-Version: version B 2.10.1 6/24/83 SMI; site unitek.uucp
- Path:sdcsvax!sdcrdcf!hplabs!qantel!ihnp4!alberta!ubc-vision!unitek
- !honman
- From: honman@unitek.uucp (Man Wong)
- Newsgroups: net.unix-wizards
- Subject: foreground -> background ?
- Message-ID: <167@unitek.uucp>
- Date: 25 Sep 85 23:51:52 GMT
- Date-Received: 29 Sep 85 09:54:48 GMT
- Reply-To: honman@unitek.UUCP (Hon-Man Wong)
- Distribution: net.all
- Organization: Unitek Technologies Corporation
- Lines: 12
-
- I have a process (C program) which generates a child and waits for
- it to return. What I would like to do is to be able to run the
- child process interactively for a while before kicking itself into
- the background so I can return to the parent process (while the
- child process is RUNNING in the background). Can it be done? And
- if it can, how?
-
- Please reply by E-mail. Thanks in advance.
-
- Hon-Man Wong
-
-
-
-
-
-
-
-
-
-
-
-Kantor & Lapsley [Page 26]
-
-
-
-RFC 977 February 1986
-Network News Transfer Protocol
-
-
-5. References
-
- [1] Crocker, D., "Standard for the Format of ARPA Internet Text
- Messages", RFC-822, Department of Electrical Engineering,
- University of Delaware, August, 1982.
-
- [2] Horton, M., "Standard for Interchange of USENET Messages",
- RFC-850, USENET Project, June, 1983.
-
- [3] Postel, J., "Transmission Control Protocol- DARPA Internet
- Program Protocol Specification", RFC-793, USC/Information
- Sciences Institute, September, 1981.
-
- [4] Postel, J., "Simple Mail Transfer Protocol", RFC-821,
- USC/Information Sciences Institute, August, 1982.
-
-6. Acknowledgements
-
- The authors wish to express their heartfelt thanks to those many
- people who contributed to this specification, and especially to Erik
- Fair and Chuq von Rospach, without whose inspiration this whole thing
- would not have been necessary.
-
-7. Notes
-
- <1> UNIX is a trademark of Bell Laboratories.
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-Kantor & Lapsley [Page 27]
-
|