rfc977.txt

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   <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 <[e-mail]> article retrieved - statistics
           only (article 10110 selected, its message-id is
           <[e-mail]>)

   (client examines the header)
   C:      HEAD
   S:      221 10110 <[e-mail]> 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 <[e-mail]> 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 <[e-mail]> 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