rfc733.txt

RFC 相关的技术文档

4.  User-defined-field

Individual users of network mail  are  free  to  define  and  use
additional  header fields.  Such fields must have names which are
not  already  used  in  the  current  specification  or  in   any
definitions  of extension-fields, and the overall syntax of these
user-defined-fields must conform to  this  specification's  rules
for  delimiting and  folding  fields.  Due to the extension-field
publishing process, the name of a user-defined-field may be  pre-
empted.




Standard for the Format of Text Messages                       24
IV. Semantics
 D. Dates



D.  DATES AND TIMES

If included, day-of-week must be the  day  implied  by  the  date
specification.

Time zone  may  be  indicated  in  several  ways.   The  military
standard   uses  a  single  character  for  each  zone.   "Z"  is
Greenwhich Mean Time; "A" indicates one  hour  earlier,  and  "M"
indicates  12 hours earlier; "N" is one hour later, and "Y" is 12
hours later.  The letter "J" is not used.   The  other  remaining
two  forms  are  taken from ANSI standard X3.51-1975.  One allows
explicit indication of the amount of offset from GMT;  the  other
uses  common  3-character  strings  for  indicating time zones in
North America.


Standard for the Format of Text Messages                       25
V. Examples
A. Addresses





                          V.  EXAMPLES


A.  ADDRESSES


1.  Alfred E. Neuman <Neuman at BBN-TENEXA>

2.  Neuman@BBN-TENEXA

These two "Alfred E. Neuman" examples have  identical  semantics,
as  far  as  the  operation  of  the  local  host's  mail sending
(distribution) program (also sometimes called its  "mailer")  and
the  remote  host's  FTP  server  are  concerned.   In  the first
example, the "Alfred E. Neuman" is  ignored  by  the  mailer,  as
"Neuman  at  BBN-TENEXA" completely specifies the recipient.  The
second example contains no superfluous information,  and,  again,
"Neuman@BBN-TENEXA" is the intended recipient.


3.  Al Neuman at BBN-TENEXA

This is identical to "Al Neuman <Al Neuman at BBN-TENEXA>".  That
is,  the  full  phrase, "Al Neuman", is passed to the FTP server.
Note that not all FTP servers accept multi-word identifiers;  and
some  that  do  accept  them  will treat each word as a different
addressee (in this case, attempting to send a copy of the message
to "Al" and a copy to "Neuman").


4.  "George Lovell, Ted Hackle" <Shared-Mailbox at Office-1>

This form might be used to indicate  that  a  single  mailbox  is
shared  by  several  users.   The quoted string is ignored by the
originating  host's  mailer,  as  "Shared-Mailbox  at   Office-1"
completely specifies the destination mailbox.


4.  Wilt (the Stilt) Chamberlain at NBA

The "(the Stilt)" is a comment, which  is  NOT  included  in  the
destination  mailbox  address  handed to the originating system's
mailer.  The  address  is  the  string  "Wilt Chamberlain",  with
exactly  one  space  between  the  first  and second words.  (The
quotation marks are not included.)




Standard for the Format of Text Messages                       26
V. Examples
B. Address Lists



B.  ADDRESS LISTS

    Gourmets:  Pompous Person <WhoZiWhatZit at Cordon-Bleu>,
               Cooks:  Childs at WGBH, Galloping Gourmet at
                       ANT (Australian National Television);,
               Wine Lovers:  Cheapie at Discount-Liquors,
                             Port at Portugal;;,
    Jones at SEA

This group list example points  out  the  use  of  comments,  the
nesting  of groups, and the mixing of addresses and groups.  Note
that the two consecutive semi-colons  preceding  "Jones  at  SEA"
mean that Jones is NOT a member of the Gourmets group.


C.  ORIGINATOR ITEMS


1.  Author-sent

George Jones logs into  his  Host  as  "Jones".   He  sends  mail
himself.

    From:  Jones at Host
or
    From:  George Jones <Jones at Host>


2.  Secretary-sent

George Jones logs in as Jones on his Host.   His  secretary,  who
logs in as Secy on Shost sends mail for him.  Replies to the mail
should go to George, of course.

    From:    George Jones <Jones at Host>
    Sender:  Secy at SHost


3.  Shared directory or unrepresentative directory-name

George Jones logs in as Group at Host.  He  sends  mail  himself;
replies should go to the Group mailbox.

    From:  George Jones <Group at Host>



Standard for the Format of Text Messages                       27
V. Examples
C. Originator Items



4.  Secretary-sent, for user of shared directory

George Jones' secretary sends mail for George in his capacity  as
a  member  of  Group  while  logged  in as Secy at Host.  Replies
should go to Group.

    From:   George Jones<Group at Host>
    Sender: Secy at Host

Note that there need not be a space between "Jones" and the  "<",
but  adding a space enhances readability (as is the case in other
examples).


5.  Secretary acting as full agent of author

George Jones asks his secretary (Secy at Host) to send a  message
for  him  in  his  capacity  as Group.  He wants his secretary to
handle all replies.

    From:     George Jones <Group at Host>
    Sender:   Secy at Host
    Reply-To: Secy at Host


6.  Agent for user without online mailbox

A  non-ARPANET  user  friend  of  George's,  Sarah,  is  visting.
George's  secretary  sends  some  mail  to  a  friend of Sarah in
computer-land.  Replies should go to  George,  whose  mailbox  is
Jones at Host.

    From:     Sarah Friendly
    Sender:   Secy at Host
    Reply-To: Jones at Host


7.  Sent by member of a committee

George is a member of a committee.  He wishes to have any replies
to his message go to all committee members.

    From:     George Jones
    Sender:   Jones at Host
    Reply-To: Big-committee: Jones at Host,
                             Smith at Other-Host,
                             Doe at Somewhere-Else;

Note that if George had not included himself in  the  enumeration
of Big-committee, he would not have gotten an implicit reply; the
presence  of  the  "Reply-to"  field  SUPERSEDES the sending of a
reply to the person named in the "From" field.

Standard for the Format of Text Messages                       28
V. Examples
C. Originator Items



8.  Example of INCORRECT use

George desires a reply to go  to  his  secretary;  therefore  his
secretary  leaves  his  mailbox  address  off  the  "From" field,
leaving only his name, which is not, itself, a mailbox address.

         From:   George Jones
         Sender: Secy at SHost

THIS IS NOT PERMITTED.  Replies are NEVER implicitly sent to  the
"Sender";  George's  secretary  should  have  used the "Reply-To"
field, or the  mail  creating  program  should  have  forced  the
secretary to.

9.  Agent for member of a committee

George's secretary sends out a message which was authored jointly
by all the members of the "Big-committee".

         From:   Big-committee: Jones at Host,
                                Smith at Other-Host,
                                Doe at Somewhere-Else;
         Sender: Secy at SHost



D.  COMPLETE HEADERS


1.  Minimum required:

       Date:  26 August 1976 1429-EDT
       From:  Jones at Host


2.  Using some of the additional fields:

       Date: 26 August 1976 1430-EDT
       From:George Jones<Group at Host>
       Sender:Secy at SHOST
       To:Al Neuman at Mad-Host,
                Sam Irving at Other-Host
       Message-ID:  <some string at SHOST>



Standard for the Format of Text Messages                       29
V. Examples
D.  Complete Headers



3.  About as complex as you're going to get:

       Date     :  27 Aug 1976 0932-PDT
       From     :  Ken Davis <KDavis at Other-Host>
       Subject  :  Re: The Syntax in the RFC
       Sender   :  KSecy at Other-Host
       Reply-To :  Sam Irving at Other-Host
       To       :  George Jones <Group at Host>,
                   Al Neuman at Mad-Host
       cc       :  Important folk:
                   Tom Softwood <Balsa at Another-Host>,
                   Sam Irving at Other-Host;,
                   Standard Distribution::Include:
                    </main/davis/people/standard at Other-Host,
                     "<Jones>standard.dist.3" at Tops-20-Host>,
                   (The following Included Postal list is part
                   of Standard Distribution.)
                   :Postal::Include: Non-net-addrs@Other-host;,
                   :Postal: "Sam Irving, P.O. Box 001, Las Vegas,
                             Nevada"  (So that he can stay
                             apprised of the situation)
       Comment  :  Sam is away on business. He asked me to handle
                   his mail for him.  He'll be able to provide  a
                   more  accurate  explanation  when  he  returns
                   next week.
       In-Reply-To: <some string at SHOST>
       Special (action):  This is a sample of multi-word field-
                   names, using a range of characters.  There
                   could also be a field-name "Special (info)".
       Message-ID: <4231.629.XYzi-What at Other-Host>


Standard for the Format of Text Messages                       31
Appendix
A. Alphabetical Listing of Syntax Rules





                        APPENDIX



A.  ALPHABETICAL LISTING OF SYNTAX RULES


address     =  host-phrase / quoted-string
            / (*phrase "<" #address ">" )
            / (*phrase ":" #address ";" )
            / (":" ("Include" / "Postal" / atom) ":" address)
ALPHA       =  <any TELNET ASCII alphabetic character>
atom        =  1*<any CHAR except specials and CTLs>

CHAR        =  <any TELNET ASCII character>
comment     =  "(" *(ctext / comment / quoted-pair) ")"
CR          =  <TELNET ASCII carriage return>
CRLF        =  CR LF
ctext       =  <any CHAR excluding "(", ")", CR, LF and
               including linear-white-space>
CTL         =  <any TELNET ASCII control character and DEL>

date        =  1*2DIGIT ["-"] month ["-"] (2DIGIT /4DIGIT)
date-field  =  "Date"       ":" date-time
date-time   =  [ day-of-week "," ] date time
day-of-week =  "Monday"    / "Mon"  / "Tuesday"   / "Tue"
            /  "Wednesday" / "Wed"  / "Thursday"  / "Thu"
            /  "Friday"    / "Fri"  / "Saturday"  / "Sat"
            /  "Sunday"    / "Sun"
delimiters  =  specials / comment / linear-white-space
DIGIT       =  <any TELNET ASCII digit>

extension-field = <Any field which is defined in a document
               published as a formal extension to this
               specification>

field       =  field-name ":" [ field-body ] CRLF

fields      =  date-field  originator-fields  *optional-field
field-body  =  field-body-contents
               [CRLF LWSP-char field-body]
field-body-contents = <the TELNET ASCII characters making up the
               field-body, as defined in the following sections,
               and consisting of combinations of atom, quoted-