< draft-gellens-format-05.txt		draft-gellens-format-06.txt >
	Internet Draft: The Text/Plain Format Parameter R. Gellens, Editor		Internet Draft: The Text/Plain Format Parameter R. Gellens, Editor
	Document: draft-gellens-format-05.txt Qualcomm		Document: draft-gellens-format-06.txt Qualcomm
	Expires: 30 September 1999 31 March 1999		Expires: 7 November 1999 7 May 1999
	Updates: RFC 2046		Updates: RFC 2046
	The Text/Plain Format Parameter		The Text/Plain Format Parameter
	Status of this Memo:		Status of this Memo:
	This document is an Internet-Draft and is in full conformance with		This document is an Internet-Draft and is in full conformance with
	all provisions of Section 10 of RFC2026.		all provisions of Section 10 of RFC2026.
	Internet-Drafts are working documents of the Internet Engineering		Internet-Drafts are working documents of the Internet Engineering
	Task Force (IETF), its areas, and its working groups. Note that		Task Force (IETF), its areas, and its working groups. Note that
	other groups may also distribute working documents as		other groups may also distribute working documents as
	Internet-Drafts.		Internet-Drafts.
	Internet-Drafts are draft documents valid for a maximum of six		Internet-Drafts are draft documents valid for a maximum of six
	months and may be updated, replaced, or obsoleted by other documents		months and may be updated, replaced, or obsoleted by other documents
	at any time. It is inappropriate to use Internet- Drafts as		at any time. It is inappropriate to use Internet- Drafts as
	reference material or to cite them other than as 'work in progress.'		reference material or to cite them other than as "work in progress."
	The list of current Internet-Drafts can be accessed at		The list of current Internet-Drafts can be accessed at
	<http://www.ietf.org/ietf/1id-abstracts.txt>		<http://www.ietf.org/ietf/1id-abstracts.txt>
	The list of Internet-Draft Shadow Directories can be accessed at		The list of Internet-Draft Shadow Directories can be accessed at
	<http://www.ietf.org/shadow.html>.		<http://www.ietf.org/shadow.html>.
	A version of this draft document is intended for submission to the		A version of this draft document is intended for submission to the
	RFC editor as a Proposed Standard for the Internet Community.		RFC editor as a Proposed Standard for the Internet Community.
	Discussion and suggestions for improvement are requested.		Discussion and suggestions for improvement are requested.
	skipping to change at line 52 ¶		skipping to change at line 51 ¶
	Copyright Notice		Copyright Notice
	Copyright (C) The Internet Society 1999. All Rights Reserved.		Copyright (C) The Internet Society 1999. All Rights Reserved.
	Table of Contents		Table of Contents
	1. Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . 2		1. Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . 2
	2. Conventions Used in this Document . . . . . . . . . . . . . 3		2. Conventions Used in this Document . . . . . . . . . . . . . 3
	3. The Problem . . . . . . . . . . . . . . . . . . . . . . . . 3		3. The Problem . . . . . . . . . . . . . . . . . . . . . . . . 3
	3.1. Paragraph Text . . . . . . . . . . . . . . . . . . . . 3		3.1. Paragraph Text . . . . . . . . . . . . . . . . . . . . 3
	3.2. Embarrassing Line Wrap . . . . . . . . . . . . . . . . . 4		3.2. Embarrassing Line Wrap . . . . . . . . . . . . . . . . . 3
	3.3. New Media Types . . . . . . . . . . . . . . . . . . . . 5		3.3. New Media Types . . . . . . . . . . . . . . . . . . . . 4
	4. The Format Parameter to the Text/Plain Media Type . . . . . 5		4. The Format Parameter to the Text/Plain Media Type . . . . . 5
	4.1. Generating Format=Flowed . . . . . . . . . . . . . . . 6		4.1. Generating Format=Flowed . . . . . . . . . . . . . . . 5
	4.2. Interpreting Format=Flowed . . . . . . . . . . . . . . . 6		4.2. Interpreting Format=Flowed . . . . . . . . . . . . . . . 6
	4.3. Usenet Signature Convention . . . . . . . . . . . . . . 7		4.3. Usenet Signature Convention . . . . . . . . . . . . . . 7
	4.4. Space-Stuffing . . . . . . . . . . . . . . . . . . . . . 7		4.4. Space-Stuffing . . . . . . . . . . . . . . . . . . . . . 7
	4.5. Quoting . . . . . . . . . . . . . . . . . . . . . . . . 8		4.5. Quoting . . . . . . . . . . . . . . . . . . . . . . . . 8
	4.6. Digital Signatures and Encryption . . . . . . . . . . . 9		4.6. Digital Signatures and Encryption . . . . . . . . . . . 9
	4.7. Line Analysis Table . . . . . . . . . . . . . . . . . . 9		4.7. Line Analysis Table . . . . . . . . . . . . . . . . . . 9
	4.8. Examples . . . . . . . . . . . . . . . . . . . . . . . . 10		4.8. Examples . . . . . . . . . . . . . . . . . . . . . . . . 10
	5. ABNF . . . . . . . . . . . . . . . . . . . . . . . . . . . 10		5. ABNF . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
	6. Failure Modes . . . . . . . . . . . . . . . . . . . . . . . 11		6. Failure Modes . . . . . . . . . . . . . . . . . . . . . . . 11
	6.1. Trailing White Space Corruption . . . . . . . . . . . . 11		6.1. Trailing White Space Corruption . . . . . . . . . . . . 11
	7. Security Considerations . . . . . . . . . . . . . . . . . . 11		7. Security Considerations . . . . . . . . . . . . . . . . . . 11
	8. IANA Considerations . . . . . . . . . . . . . . . . . . . . 11		8. IANA Considerations . . . . . . . . . . . . . . . . . . . . 11
	9. Internationalization Considerations . . . . . . . . . . . . 12		9. Internationalization Considerations . . . . . . . . . . . . 11
	10. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . 12		10. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . 12
	11. References . . . . . . . . . . . . . . . . . . . . . . . . . 12		11. References . . . . . . . . . . . . . . . . . . . . . . . . . 12
	12. Editor's Address . . . . . . . . . . . . . . . . . . . . . 12		12. Editor's Address . . . . . . . . . . . . . . . . . . . . . 12
	13. Full Copyright Statement . . . . . . . . . . . . . . . . . . 13		13. Full Copyright Statement . . . . . . . . . . . . . . . . . . 12
	1. Abstract		1. Abstract
	Interoperability problems have been observed with erroneous		Interoperability problems have been observed with erroneous
	labelling of paragraph text as Text/Plain, and with various forms of		labelling of paragraph text as Text/Plain, and with various forms of
	'embarrassing line wrap.' (See section 3.)		"embarrassing line wrap." (See section 3.)
	Attempts to deploy new media types, such as Text/Enriched [RICH] and		Attempts to deploy new media types, such as Text/Enriched [RICH] and
	Text/HTML [HTML] have suffered from a lack of backwards		Text/HTML [HTML] have suffered from a lack of backwards
	compatibility and an often hostile user reaction at the receiving		compatibility and an often hostile user reaction at the receiving
	end.		end.
	What is required is a format which is in all significant ways		What is required is a format which is in all significant ways
	Text/Plain, and therefore is quite suitable for display as		Text/Plain, and therefore is quite suitable for display as
	Text/Plain, and yet allows the sender to express to the receiver		Text/Plain, and yet allows the sender to express to the receiver
	which lines can be considered a logical paragraph, and thus flowed		which lines can be considered a logical paragraph, and thus flowed
	(wrapped and joined) as appropriate.		(wrapped and joined) as appropriate.
	This memo proposes a new parameter to be used with Text/Plain, and,		This memo proposes a new parameter to be used with Text/Plain, and,
	in the presence of this parameter, the use of trailing whitespace to		in the presence of this parameter, the use of trailing whitespace to
	indicate flowed lines. This results in an encoding which appears as		indicate flowed lines. This results in an encoding which appears as
	normal Text/Plain in older implementations, since it is in fact		normal Text/Plain in older implementations, since it is in fact
	normal Text/Plain.		normal Text/Plain.
	2. Conventions Used in this Document		2. Conventions Used in this Document
	The key words 'REQUIRED', 'MUST', 'MUST NOT', 'SHOULD', 'SHOULD		The key words "REQUIRED", "MUST", "MUST NOT", "SHOULD", "SHOULD
	NOT', and 'MAY' in this document are to be interpreted as described		NOT", and "MAY" in this document are to be interpreted as described
	in 'Key words for use in RFCs to Indicate Requirement Levels'		in "Key words for use in RFCs to Indicate Requirement Levels"
	[KEYWORDS].		[KEYWORDS].
	3. The Problem		3. The Problem
	The Text/Plain media type is the lowest common denominator of		The Text/Plain media type is the lowest common denominator of
	Internet email, with lines of no more than 997 characters (by		Internet email, with lines of no more than 997 characters (by
	convention usually no more than 80), and where the CRLF sequence		convention usually no more than 80), and where the CRLF sequence
	represents a line break [MIME-IMT].		represents a line break [MIME-IMT].
	Text/Plain is usually displayed as preformatted text, often in a		Text/Plain is usually displayed as preformatted text, often in a
	fixed font. That is, the characters start at the left margin of the		fixed font. That is, the characters start at the left margin of the
	display window, and advance to the right until a CRLF sequence is		display window, and advance to the right until a CRLF sequence is
	seen, at which point a new line is started, again at the left		seen, at which point a new line is started, again at the left
	margin. When a line length exceeds the display window, some clients		margin. When a line length exceeds the display window, some clients
	will wrap the line, while others invoke a horizontal scroll bar.		will wrap the line, while others invoke a horizontal scroll bar.
	Text which meets this description is defined by this memo as		Text which meets this description is defined by this memo as
	'fixed'.		"fixed".
	Some interoperability problems have been observed with this media		Some interoperability problems have been observed with this media
	type:		type:
	3.1. Paragraph Text		3.1. Paragraph Text
	Many modern programs use a proportional-spaced font and CRLF to		Many modern programs use a proportional-spaced font and CRLF to
	represent paragraph breaks. Line breaks are 'soft', occurring as		represent paragraph breaks. Line breaks are "soft", occurring as
	needed on display. That is, characters are grouped into a paragraph		needed on display. That is, characters are grouped into a paragraph
	until a CRLF sequence is seen, at which point a new paragraph is		until a CRLF sequence is seen, at which point a new paragraph is
	started. Each paragraph is displayed, starting at the left margin		started. Each paragraph is displayed, starting at the left margin
	(or paragraph indent), and continuing to the right until a word is		(or paragraph indent), and continuing to the right until a word is
	encountered which does not fit in the remaining display width. This		encountered which does not fit in the remaining display width. This
	word is displayed at the left margin of the next line. This		word is displayed at the left margin of the next line. This
	continues until the paragraph ends (a CRLF is seen). Extra vertical		continues until the paragraph ends (a CRLF is seen). Extra vertical
	space is left between paragraphs.		space is left between paragraphs.
	Text which meets this description is defined by this memo as		Text which meets this description is defined by this memo as
	'flowed'.		"flowed".
	Numerous software products erroneously label this media type as		Numerous software products erroneously label this media type as
	Text/Plain, resulting in much user discomfort.		Text/Plain, resulting in much user discomfort.
	3.2. Embarrassing Line Wrap		3.2. Embarrassing Line Wrap
	As Text/Plain messages get quoted in replies or forwarded messages,		As Text/Plain messages get quoted in replies or forwarded messages,
	the length of each line gradually increases, resulting in		the length of each line gradually increases, resulting in
	'embarrassing line wrap.' This results in text which is at best hard		"embarrassing line wrap." This results in text which is at best hard
	to read, and often confuses attributions.		to read, and often confuses attributions.
	Example:		Example:
	>>>>>>This is a comment from the first message to show a		>>>>>>This is a comment from the first message to show a
	>quoting example.		>quoting example.
	>>>>>This is a comment from the second message to show a		>>>>>This is a comment from the second message to show a
	>quoting example.		>quoting example.
	>>>>This is a comment from the third message.		>>>>This is a comment from the third message.
	>>>This is a comment from the fourth message.		>>>This is a comment from the fourth message.
	skipping to change at line 184 ¶		skipping to change at line 184 ¶
	PDA with only		PDA with only
	30 character lines.		30 character lines.
	3.3. New Media Types		3.3. New Media Types
	Attempts to deploy new media types, such as Text/Enriched [RICH] and		Attempts to deploy new media types, such as Text/Enriched [RICH] and
	Text/HTML [HTML] have suffered from a lack of backwards		Text/HTML [HTML] have suffered from a lack of backwards
	compatibility and an often hostile user reaction at the receiving		compatibility and an often hostile user reaction at the receiving
	end.		end.
	In particular, Text/Enriched requires that open angle brackets ('<')		In particular, Text/Enriched requires that open angle brackets ("<")
	and hard line breaks be doubled, with resulting user unhappiness		and hard line breaks be doubled, with resulting user unhappiness
	when viewed as Text/Plain. Text/HTML requires even more alteration		when viewed as Text/Plain. Text/HTML requires even more alteration
	of text, with a corresponding increase in user complaints.		of text, with a corresponding increase in user complaints.
	A proposal to define a new media type to explicitly represent the		A proposal to define a new media type to explicitly represent the
	paragraph form suffered from a lack of interoperability with		paragraph form suffered from a lack of interoperability with
	currently deployed software. Some programs treat unknown subtypes		currently deployed software. Some programs treat unknown subtypes
	of TEXT as an attachment.		of TEXT as an attachment.
	What is desired is a format which is in all significant ways		What is desired is a format which is in all significant ways
	skipping to change at line 237 ¶		skipping to change at line 237 ¶
	4.1. Generating Format=Flowed		4.1. Generating Format=Flowed
	When generating Format=Flowed text, lines SHOULD be shorter than 80		When generating Format=Flowed text, lines SHOULD be shorter than 80
	characters. As suggested values, any paragraph longer than 79		characters. As suggested values, any paragraph longer than 79
	characters in total length could be wrapped using lines of 72 or		characters in total length could be wrapped using lines of 72 or
	fewer characters. While the specific line length used is a matter		fewer characters. While the specific line length used is a matter
	of aesthetics and preference, longer lines are more likely to		of aesthetics and preference, longer lines are more likely to
	require rewrapping and to encounter difficulties with older mailers.		require rewrapping and to encounter difficulties with older mailers.
	It has been suggested that 66 character lines are the most readable.		It has been suggested that 66 character lines are the most readable.
			(The reason for the restriction to 79 or fewer characters between
			CRLFs on the wire is to ensure that all lines, even when displayed
			by a non-flowed-aware program, will fit in a standard 80-column
			screen without having to be wrapped. The limit is 79, not 80,
			because while 80 fit on a line, the last column is often reserved
			for a line-wrap indicator.)
	When creating flowed text, the generating agent wraps, that is,		When creating flowed text, the generating agent wraps, that is,
	inserts 'soft' line breaks (SP CRLF sequences) as needed. Soft line		inserts 'soft' line breaks as needed. Soft line breaks are added
	breaks are added between words.		between words. Because a soft line break is a SP CRLF sequence, the
			generating agent creates one by inserting a CRLF after the occurance
			of a space.
			A generating agent SHOULD NOT insert white space into a word (a
			sequence of printable characters not containing spaces). If faced
			with a word which exceeds 79 characters (but less than 998
			characters, the SMTP limit on line length), the agent SHOULD send
			the word as is and exceed the 79-character limit on line length.
	A generating agent SHOULD:		A generating agent SHOULD:
	1. Ensure all lines (fixed and flowed) are less than 80		1. Ensure all lines (fixed and flowed) are 79 characters or
	characters in length, not counting the CRLF.		less in length, counting the trailing space but not
			counting the CRLF, unless a word by itself exceeds 79
			characters.
	2. Trim spaces before user-inserted hard line breaks.		2. Trim spaces before user-inserted hard line breaks.
	3. Space-stuff lines which start with a space, 'From ', or		3. Space-stuff lines which start with a space, "From ", or
	'>'.		">".
	In order to create messages which do not require space-stuffing, and		In order to create messages which do not require space-stuffing, and
	are thus more aesthetically pleasing when viewed as Format=Fixed, a		are thus more aesthetically pleasing when viewed as Format=Fixed, a
	generating agent MAY avoid wrapping immediately before '>', 'From ',		generating agent MAY avoid wrapping immediately before ">", "From ",
	or space.		or space.
	(See sections 4.4 and 4.5 for more information on space-stuffing and		(See sections 4.4 and 4.5 for more information on space-stuffing and
	quoting, respectively.)		quoting, respectively.)
	A Format=Flowed message consists of zero or more paragraphs, each		A Format=Flowed message consists of zero or more paragraphs, each
	containing one or more flowed lines followed by one fixed line. The		containing one or more flowed lines followed by one fixed line. The
	usual case is a series of flowed text lines with blank (empty) fixed		usual case is a series of flowed text lines with blank (empty) fixed
	lines between them.		lines between them.
	skipping to change at line 277 ¶		skipping to change at line 294 ¶
	for the sole purpose of protecting the trailing space on flowed		for the sole purpose of protecting the trailing space on flowed
	lines unless the body part is cryptographically signed or encrypted		lines unless the body part is cryptographically signed or encrypted
	(see Section 4.6).		(see Section 4.6).
	The intent of Format=Flowed is to allow user agents to generate		The intent of Format=Flowed is to allow user agents to generate
	flowed text which is non-obnoxious when viewed as pure, raw		flowed text which is non-obnoxious when viewed as pure, raw
	Text/Plain (without any decoding); use of Quoted-Printable hinders		Text/Plain (without any decoding); use of Quoted-Printable hinders
	this and may cause Format=Flowed to be rejected by end users.		this and may cause Format=Flowed to be rejected by end users.
	4.2. Interpreting Format=Flowed		4.2. Interpreting Format=Flowed
	If the first character of a line is a quote mark ('>'), the line is
			If the first character of a line is a quote mark (">"), the line is
	considered to be quoted (see section 4.5). Logically, all quote		considered to be quoted (see section 4.5). Logically, all quote
	marks are counted and deleted, resulting in a line with a non-zero		marks are counted and deleted, resulting in a line with a non-zero
	quote depth, and content. (The agent is of course free to display		quote depth, and content. (The agent is of course free to display
	the content with quote marks or excerpt bars or anything else.)		the content with quote marks or excerpt bars or anything else.)
	Logically, this test for quoted lines is done before any other tests		Logically, this test for quoted lines is done before any other tests
	(that is, space-stuffed and flowed).		(that is, before checking for space-stuffed and flowed).
	If the first character of a line is a space, the line has been		If the first character of a line is a space, the line has been
	space-stuffed (see section 4.4). Logically, this leading space is		space-stuffed (see section 4.4). Logically, this leading space is
	deleted before examining the line further (that is, before checking		deleted before examining the line further (that is, before checking
	for flowed).		for flowed).
	If the line ends in one or more spaces, the line is flowed.		If the line ends in one or more spaces, the line is flowed.
	Otherwise it is fixed.		Otherwise it is fixed. Trailing spaces are part of the line's
			content, but the CRLF of a soft line break is not.
	A series of one or more flowed lines followed by one fixed line is		A series of one or more flowed lines followed by one fixed line is
	considered a paragraph, and MAY be flowed (wrapped and unwrapped) as		considered a paragraph, and MAY be flowed (wrapped and unwrapped) as
	appropriate on display and in the construction of new messages (see		appropriate on display and in the construction of new messages (see
	section 4.5).		section 4.5).
	A line consisting of one or more spaces (after deleting a stuffed		A line consisting of one or more spaces (after deleting a stuffed
	space) is considered a flowed line.		space) is considered a flowed line.
	4.3. Usenet Signature Convention		4.3. Usenet Signature Convention
	There is a convention in Usenet news of using '-- ' as the separator		There is a convention in Usenet news of using "-- " as the separator
	line between the body and the signature of a message. When		line between the body and the signature of a message. When
	generating a Format=Flowed message containing a Usenet-style		generating a Format=Flowed message containing a Usenet-style
	separator before the signature, the separator line is sent as-is.		separator before the signature, the separator line is sent as-is.
	This is a special case; an (optionally quoted) line consisting of		This is a special case; an (optionally quoted) line consisting of
	DASH DASH SP is not considered flowed.		DASH DASH SP is not considered flowed.
	4.4. Space-Stuffing		4.4. Space-Stuffing
	In order to allow for unquoted lines which start with '>', and to		In order to allow for unquoted lines which start with ">", and to
	protect against systems which 'From-munge' in-transit messages		protect against systems which "From-munge" in-transit messages
	(modifying any line which starts with 'From ' to '>From '),		(modifying any line which starts with "From " to ">From "),
	Format=Flowed provides for space-stuffing.		Format=Flowed provides for space-stuffing.
	Space-stuffing adds a single space to the start of any line which		Space-stuffing adds a single space to the start of any line which
	needs protection when the message is generated. On reception, if		needs protection when the message is generated. On reception, if
	the first character of a line is a space, it is logically deleted.		the first character of a line is a space, it is logically deleted.
	This occurs after the test for a quoted line, and before the test		This occurs after the test for a quoted line, and before the test
	for a flowed line.		for a flowed line.
	On generation, unquoted lines which start with '>', and any line		On generation, any unquoted lines which start with ">", and any
	which starts with a space or 'From ' needs to be space-stuffed.		lines which start with a space or "From " SHOULD be space-stuffed.
	Other lines MAY be space-stuffed as desired.		Other lines MAY be space-stuffed as desired.
	Note that space-stuffing is very similar to dot-stuffing as		(Note that space-stuffing is similar to dot-stuffing as specified in
	specified in [SMTP].		[SMTP].)
	If a space-stuffed message is received by an agent which handles		If a space-stuffed message is received by an agent which handles
	Format=Flowed, the space-stuffing is reversed and thus the message		Format=Flowed, the space-stuffing is reversed and thus the message
	appears unchanged. An agent which is not aware of Format=Flowed		appears unchanged. An agent which is not aware of Format=Flowed
	will of course not undo any space-stuffing, thus Format=Flowed		will of course not undo any space-stuffing, thus Format=Flowed
	messages may appear with a leading space on some lines (those which		messages may appear with a leading space on some lines (those which
	start with a space or a '>' which is not a quote indicator). Since		start with a space, ">" which is not a quote indicator, or "From ").
	lines which require space-stuffing rarely occur, and the aesthetic
	consequences of unreversed space-stuffing are minimal, this is not		Since lines which require space-stuffing rarely occur, and the
	expected to be a significant problem.		aesthetic consequences of unreversed space-stuffing are minimal,
			this is not expected to be a significant problem.
	4.5. Quoting		4.5. Quoting
	In Format=Flowed, the canonical quote indicator (or quote mark) is		In Format=Flowed, the canonical quote indicator (or quote mark) is
	one or more close angle bracket ('>') characters. Lines which start		one or more close angle bracket (">") characters. Lines which start
	with the quote indicator are considered quoted. The number of '>'		with the quote indicator are considered quoted. The number of ">"
	characters at the start of the line specifies the quote depth.		characters at the start of the line specifies the quote depth.
	Flowed lines which are also quoted may require special handling on		Flowed lines which are also quoted may require special handling on
	display and when copied to new messages.		display and when copied to new messages.
	When creating quoted flowed lines, each such line starts with the		When creating quoted flowed lines, each such line starts with the
	quote indicator.		quote indicator.
	Note that because of space-stuffing, the lines		Note that because of space-stuffing, the lines
	>> Exit, Stage Left		>> Exit, Stage Left
	and		and
	>>Exit, Stage Left		>>Exit, Stage Left
	are semantically identical; both have a quote-depth of two, and a		are semantically identical; both have a quote-depth of two, and a
	content of 'Exit, Stage Left'.		content of "Exit, Stage Left".
	However, the line		However, the line
	> > Exit, Stage Left		> > Exit, Stage Left
	is different. It has a quote-depth of one, and a content of		is different. It has a quote-depth of one, and a content of
	'> Exit, Stage Left'.		"> Exit, Stage Left".
	When generating quoted flowed lines, an agent needs to pay attention		When generating quoted flowed lines, an agent needs to pay attention
	to changes in quote depth. A sequence of quoted lines of the same		to changes in quote depth. A sequence of quoted lines of the same
	quote depth SHOULD be encoded as a paragraph, with the last line		quote depth SHOULD be encoded as a paragraph, with the last line
	generated as fixed and prior lines generated as flowed.		generated as fixed and prior lines generated as flowed.
	If a receiving agent wishes to reformat flowed quoted lines (joining		If a receiving agent wishes to reformat flowed quoted lines (joining
	and/or wrapping them) on display or when generating new messages,		and/or wrapping them) on display or when generating new messages,
	the lines SHOULD be de-quoted, reformatted, and then re-quoted. To		the lines SHOULD be de-quoted, reformatted, and then re-quoted. To
	de-quote, the number of close angle brackets in the quote indicator		de-quote, the number of close angle brackets in the quote indicator
	skipping to change at line 463 ¶		skipping to change at line 483 ¶
	`You mean you can't take LESS,' said the Hatter: `it's very easy		`You mean you can't take LESS,' said the Hatter: `it's very easy
	to take MORE than nothing.'		to take MORE than nothing.'
	This could be encoded as follows (using '*' to indicate a soft line		This could be encoded as follows (using '*' to indicate a soft line
	break, that is, SP CRLF sequence, and '#' to indicate a hard line		break, that is, SP CRLF sequence, and '#' to indicate a hard line
	break, that is, CRLF):		break, that is, CRLF):
	`Take some more tea,' the March Hare said to Alice, very*		`Take some more tea,' the March Hare said to Alice, very*
	earnestly.#		earnestly.#
	#		#
	`I've had nothing yet,' Alice replied in an offended tone, `so* I		`I've had nothing yet,' Alice replied in an offended tone, `so*
	can't take more.'#		I can't take more.'#
	#		#
	`You mean you can't take LESS,' said the Hatter: `it's very* easy		`You mean you can't take LESS,' said the Hatter: `it's very*
	to take MORE than nothing.'#		easy to take MORE than nothing.'#
	Here we have the same exchange, in quoted form:		Here we have the same exchange, in quoted form:
	>>>Take some more tea.#		>>>Take some more tea.#
	>>I've had nothing yet, so I can't take more.#		>>I've had nothing yet, so I can't take more.#
	>You mean you can't take LESS, it's very easy to take*		>You mean you can't take LESS, it's very easy to take*
	>MORE than nothing.#		>MORE than nothing.#
	5. ABNF		5. ABNF
	skipping to change at line 490 ¶		skipping to change at line 510 ¶
	paragraph = 1*flowed-line fixed-line		paragraph = 1*flowed-line fixed-line
	fixed-line = fixed / sig-sep		fixed-line = fixed / sig-sep
	fixed = [quote] [stuffing] *text-char non-sp CRLF		fixed = [quote] [stuffing] *text-char non-sp CRLF
	flowed-line = flow-qt / flow-unqt		flowed-line = flow-qt / flow-unqt
	flow-qt = quote [stuffing] *text-char 1*SP CRLF		flow-qt = quote [stuffing] *text-char 1*SP CRLF
	flow-unqt = [stuffing] *text-char 1*SP CRLF		flow-unqt = [stuffing] *text-char 1*SP CRLF
	non-empty = *text-char non-sp		non-empty = *text-char non-sp
	non-sp = %x01-09 / %x0B / %x0C / %x0E-1F / %x21-7F		non-sp = %x01-09 / %x0B / %x0C / %x0E-1F / %x21-7F
	; any 7-bit US-ASCII character, excluding		; any 7-bit US-ASCII character, excluding
	NUL, CR, LF, and SP		; NUL, CR, LF, and SP
	quote = 1*'>'		quote = 1*">"
	sig-sep = [quote] '--' SP CRLF		sig-sep = [quote] "--" SP CRLF
	stuffing = [SP] ; space-stuffed, added on generation if		stuffing = [SP] ; space-stuffed, added on generation if
	needed, deleted on reception		; needed, deleted on reception
	text-char = non-sp / SP		text-char = non-sp / SP
	6. Failure Modes		6. Failure Modes
	6.1. Trailing White Space Corruption		6.1. Trailing White Space Corruption
	There are systems in existence which alter trailing whitespace on		There are systems in existence which alter trailing whitespace on
	messages which pass through them. Such systems may strip, or in		messages which pass through them. Such systems may strip, or in
	rarer cases, add trailing whitespace, in violation of RFC 821 [SMTP]		rarer cases, add trailing whitespace, in violation of RFC 821 [SMTP]
	section 4.5.2.		section 4.5.2.
	skipping to change at line 538 ¶		skipping to change at line 558 ¶
	Section 4.6 discusses the interaction between Format=Flowed and		Section 4.6 discusses the interaction between Format=Flowed and
	digital signatures or encryption.		digital signatures or encryption.
	8. IANA Considerations		8. IANA Considerations
	IANA is requested to add a reference to this specification in the		IANA is requested to add a reference to this specification in the
	Text/Plain Media Type registration.		Text/Plain Media Type registration.
	9. Internationalization Considerations		9. Internationalization Considerations
	The line wrap and quoting specifications of Format=Flowed may not be		The line wrap and quoting specifications of Format=Flowed may not be
	suitable for certain charsets, such as for Arabic and Hebrew		suitable for certain charsets, such as for Arabic and Hebrew
	characters that read from right to left. Care should be taken in		characters that read from right to left. Care should be taken in
	applying format=flowed in these cases, as format=fixed combined with		applying format=flowed in these cases, as format=fixed combined with
	quoted-printable encoding may be more suitable.		quoted-printable encoding may be more suitable.
	10. Acknowledgments		10. Acknowledgments
	This proposal evolved from a discussion of Chris Newman's		This proposal evolved from a discussion of Chris Newman's
	Text/Paragraph draft which took place on the IETF 822 mailing list.		Text/Paragraph draft which took place on the IETF 822 mailing list.
	Special thanks to Ian Bell, Steve Dorner, Brian Kelley, Dan Kohn,		Special thanks to Ian Bell, Steve Dorner, Brian Kelley, Dan Kohn,
	Laurence Lundblade, and Dan Wing for their reviews, comments,		Laurence Lundblade, and Dan Wing for their reviews, comments,
	suggestions, and discussions.		suggestions, and discussions.
	11. References		11. References
	[ABNF] Crocker, Overell, 'Augmented BNF for Syntax Specifications:		[ABNF] Crocker, Overell, "Augmented BNF for Syntax Specifications:
	ABNF', RFC 2234, Internet Mail Consortium, Demon Internet Ltd.,		ABNF", RFC 2234, Internet Mail Consortium, Demon Internet Ltd.,
	November 1997.		November 1997.
	[KEYWORDS] Bradner, 'Key words for use in RFCs to Indicate		[KEYWORDS] Bradner, "Key words for use in RFCs to Indicate
	Requirement Levels', RFC 2119, Harvard University, March 1997.		Requirement Levels", RFC 2119, Harvard University, March 1997.
	[RICH] Resnick, Walker, 'The text/enriched MIME Content-type', RFC		[RICH] Resnick, Walker, "The text/enriched MIME Content-type", RFC
	1896, QUALCOMM, InterCon, February 1996.		1896, QUALCOMM, InterCon, February 1996.
	[MIME-IMT] Freed, Borenstein, 'Multipurpose Internet Mail Extensions		[MIME-IMT] Freed, Borenstein, "Multipurpose Internet Mail Extensions
	(MIME) Part Two: Media Types', RFC 2046, Innosoft, First Virtual,		(MIME) Part Two: Media Types", RFC 2046, Innosoft, First Virtual,
	November 1996.		November 1996.
	[Quoted-Printable] Freed, Borenstein, 'Multipurpose Internet Mail		[Quoted-Printable] Freed, Borenstein, "Multipurpose Internet Mail
	Extensions (MIME) Part One: Format of Internet Message Bodies', RFC		Extensions (MIME) Part One: Format of Internet Message Bodies", RFC
	2045, Innosoft, First Virtual, November 1996.		2045, Innosoft, First Virtual, November 1996.
	[SMTP] Postel, 'Simple Mail Transfer Protocol', RFC 821, Information		[SMTP] Postel, "Simple Mail Transfer Protocol", RFC 821, Information
	Sciences Institute, August 1982.		Sciences Institute, August 1982.
	12. Editor's Address		12. Editor's Address
	Randall Gellens +1 619 651 5115		Randall Gellens +1 619 651 5115
	QUALCOMM Incorporated randy@qualcomm.com		QUALCOMM Incorporated randy@qualcomm.com
	6455 Lusk Blvd.		6455 Lusk Blvd.
	San Diego, CA 92121-2779		San Diego, CA 92121-2779
	USA		USA
	skipping to change at line 585 ¶		skipping to change at line 604 ¶
	12. Editor's Address		12. Editor's Address
	Randall Gellens +1 619 651 5115		Randall Gellens +1 619 651 5115
	QUALCOMM Incorporated randy@qualcomm.com		QUALCOMM Incorporated randy@qualcomm.com
	6455 Lusk Blvd.		6455 Lusk Blvd.
	San Diego, CA 92121-2779		San Diego, CA 92121-2779
	USA		USA
	13. Full Copyright Statement		13. Full Copyright Statement
	Copyright (C) The Internet Society 1999. All Rights Reserved.		Copyright (C) The Internet Society 1999. All Rights Reserved.
	This document and translations of it may be copied and furnished to		This document and translations of it may be copied and furnished to
	others, and derivative works that comment on or otherwise explain it		others, and derivative works that comment on or otherwise explain it
	or assist in its implementation may be prepared, copied, published		or assist in its implementation may be prepared, copied, published
	and distributed, in whole or in part, without restriction of any		and distributed, in whole or in part, without restriction of any
	kind, provided that the above copyright notice and this paragraph		kind, provided that the above copyright notice and this paragraph
	are included on all such copies and derivative works. However, this		are included on all such copies and derivative works. However, this
	document itself may not be modified in any way, such as by removing		document itself may not be modified in any way, such as by removing
	the copyright notice or references to the Internet Society or other		the copyright notice or references to the Internet Society or other
	Internet organizations, except as needed for the purpose of		Internet organizations, except as needed for the purpose of
	developing Internet standards in which case the procedures for		developing Internet standards in which case the procedures for
	copyrights defined in the Internet Standards process must be		copyrights defined in the Internet Standards process must be
	followed, or as required to translate it into languages other than		followed, or as required to translate it into languages other than
	English.		English.
	The limited permissions granted above are perpetual and will not be		The limited permissions granted above are perpetual and will not be
	revoked by the Internet Society or its successors or assigns.		revoked by the Internet Society or its successors or assigns.
	This document and the information contained herein is provided on an		This document and the information contained herein is provided on an
	'AS IS' basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING		"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
	TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING		TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
	BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION		BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
	HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF		HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
	MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.		MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
	Gellens [Page 13] Expires September 1999		Gellens [Page 13] Expires November 1999
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