From b732a73bc773789894466b0e5320b2f1fe42c7e9 Mon Sep 17 00:00:00 2001 From: John Denker Date: Fri, 1 Jun 2012 18:58:45 -0700 Subject: original, as downloaded from http://www.qmail.org/netqmail-1.06.tar.gz --- qmail-header.5 | 332 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 332 insertions(+) create mode 100644 qmail-header.5 (limited to 'qmail-header.5') diff --git a/qmail-header.5 b/qmail-header.5 new file mode 100644 index 0000000..d90323a --- /dev/null +++ b/qmail-header.5 @@ -0,0 +1,332 @@ +.TH qmail-header 5 +.SH NAME +qmail-header \- format of a mail message +.SH OVERVIEW +At the top of every mail message is a +highly structured +.BR header . +Many programs expect the header to carry certain information, +as described below. +The main function of +.B qmail-inject +is to make sure that each outgoing message has an appropriate header. + +For more detailed information, see +.BR http://pobox.com/~djb/proto/immhf.html . +.SH "MESSAGE STRUCTURE" +A message contains a series of +.I header fields\fR, +a blank line, +and a +.IR body : + +.EX + Received: (qmail-queue invoked by uid 666); +.br + 30 Jul 1996 11:54:54 -0000 +.br + From: djb@silverton.berkeley.edu (D. J. Bernstein) +.br + To: fred@silverton.berkeley.edu +.br + Date: 30 Jul 1996 11:54:54 -0000 +.br + Subject: Go, Bears! +.br + +.br + I've got money on this one. How about you? +.br + +.br + ---Dan (this is the third line of the body) +.EE + +Each header field has a +.IR name , +a colon, +some +.IR contents , +and a newline: + +.EX + Subject: Go, Bears! +.EE + +The field contents may be folded across several lines. +Each line past the first must begin with a space or tab: + +.EX + Received: (qmail-queue invoked by uid 666); +.br + 30 Jul 1996 11:54:54 -0000 +.EE + +The field name must not contain spaces, tabs, or colons. +Also, an empty field name is illegal. +.B qmail-inject +does not allow field names with unprintable characters. + +Case is irrelevant in field names: +.B subject +and +.B SUBJECT +and +.B SuBjEcT +have the same meaning. +.SH "ADDRESS LISTS" +Certain fields, such as +.BR To , +contain +.I address lists\fR. + +An address list contains some number of +.I addresses +or +.I address groups\fR, +separated by commas: + +.EX + a@b, c@d (Somebody), A Person , +.br + random group: g@h, i@j;, k@l +.EE + +An +.I address group +has some text, a colon, a list of addresses, +and a semicolon: + +.EX + random group: g@h, i@j; +.EE + +An address can appear in several forms. +The most common form is +.IR box@host . + +Every address must include a host name. +If +.B qmail-inject +sees a lone box name +it adds the +.I default host name\fR. + +All host names should be fully qualified. +.B qmail-inject +appends the +.I default domain name +to any name without dots: + +.EX + djb@silverton -> djb@silverton.berkeley.edu +.EE + +It appends the +.I plus domain name +to any name +that ends with a plus sign: + +.EX + eric@mammoth.cs+ -> eric@mammoth.cs.berkeley.edu +.EE + +A host name may be a dotted-decimal address: + +.EX + djb@[128.32.183.163] +.EE + +RFC 822 allows mailbox names inside angle brackets +to include +.I source routes\fR, +but +.B qmail-inject +strips all source routes out of addresses. +.SH "SENDER ADDRESSES" +.B qmail-inject +looks for sender address lists in the following fields: +.BR Sender , +.BR From , +.BR Reply-To , +.BR Return-Path , +.BR Return-Receipt-To , +.BR Errors-To , +.BR Resent-Sender , +.BR Resent-From , +.BR Resent-Reply-To . + +If there is no +.B From +field, +.B qmail-inject +adds a new +.B From +field with the name of the user invoking +.B qmail-inject. + +RFC 822 requires that certain sender fields contain +only a single address, but +.B qmail-inject +does not enforce this restriction. +.SH "RECIPIENT ADDRESSES" +.B qmail-inject +looks for recipient address lists in the following fields: +.BR To , +.BR Cc , +.BR Bcc , +.BR Apparently-To , +.BR Resent-To , +.BR Resent-Cc , +.BR Resent-Bcc . + +Every message must contain at least one +.B To +or +.B Cc +or +.BR Bcc . +.B qmail-inject +deletes any +.B Bcc +field. +If there is no +.B To +or +.B Cc +field, +.B qmail-inject +adds a line + +.EX + Cc: recipient list not shown: ; +.EE + +This complies with RFC 822; +it also works around some strange +.B sendmail +behavior, in case the message is passed through +.B sendmail +on another machine. +.SH STAMPS +Every message must contain a +.B Date +field, with the date in a strict format defined by RFC 822. +If necessary +.B qmail-inject +creates a new +.B Date +field with the current date (in GMT). + +Every message should contain a +.B Message-Id +field. +The field contents are a unique worldwide identifier for this message. +If necessary +.B qmail-inject +creates a new +.B Message-Id +field. + +Another important field is +.BR Received . +Every time the message is sent from one system to another, +a new +.B Received +field is added to the top of the message. +.B qmail-inject +does not create any +.B Received +fields. +.SH "RESENT MESSAGES" +A message is +.I resent +if it contains any of the following fields: +.BR Resent-Sender , +.BR Resent-From , +.BR Resent-Reply-To , +.BR Resent-To , +.BR Resent-Cc , +.BR Resent-Bcc , +.BR Resent-Date , +.BR Resent-Message-ID . + +If a message is resent, +.B qmail-inject +changes its behavior as follows. + +It deletes any +.B Resent-Bcc +field (as well as any +.B Bcc +field); +if there are no +.B Resent-To +or +.B Resent-Cc +fields, +.B qmail-inject +adds an appropriate +.B Resent-Cc +line. +It does +.I not +add a +.B Cc +line, +even if neither +.B To +nor +.B Cc +is present. + +If there is no +.B Resent-From +field, +.B qmail-inject +adds a new +.B Resent-From +field. +It does +.I not +add a new +.B From +field. + +.B qmail-inject +adds +.B Resent-Date +if one is not already present; +same for +.BR Resent-Message-Id . +It does +.I not +add new +.B Date +or +.B Message-Id +fields. +.SH "OTHER FEATURES" +Addresses are separated by commas, not spaces. +When +.B qmail-inject +sees an illegal space, +it inserts a comma: + +.EX + djb fred -> djb, fred +.EE + +.B qmail-inject +removes all +.B Return-Path +header fields. + +.B qmail-inject +also removes any +.B Content-Length +fields. +.SH "SEE ALSO" +addresses(5), +envelopes(5), +qmail-inject(8) -- cgit v1.2.3