-.TH MHBUILD %manext1% "September 23, 2016" "%nmhversion%"
-.\"
+.TH MHBUILD %manext1% 2016-10-15 "%nmhversion%"
+.
.\" %nmhwarning%
-.\"
+.
.SH NAME
-mhbuild \- translate MIME composition draft
+mhbuild \- translate MIME composition drafts for nmh messages
.SH SYNOPSIS
.na
.HP 5
.B mhbuild
+.RB [ \-help ]
+.RB [ \-version ]
.I file
.RB [ \-auto " | " \-noauto ]
.RB [ \-list " | " \-nolist ]
.RB [ \-disposition " | " \-nodisposition ]
.RB [ \-check " | " \-nocheck ]
.RB [ \-headerencoding
-.IR encoding\-algorithm
+.I encoding-algorithm
.RB " | " \-autoheaderencoding ]
.RB [ \-maxunencoded
-.IR line\-length ]
+.IR line-length ]
.RB [ \-dist ]
-.RB [ \-version ]
-.RB [ \-help ]
.ad
.SH DESCRIPTION
The
.B mhbuild
-command will translate a MIME composition draft into
-a valid MIME message.
+command will translate a MIME composition draft into a valid MIME message.
.PP
.B mhbuild
-creates multi-media messages as specified in RFC 2045
-through RFC 2049.
-This includes the encoding of message headers as specified
-by RFC 2047, and the encoding of MIME parameters as specified in RFC 2231.
+creates multi-media messages as specified in RFCs 2045 through 2049.
+This includes the encoding of message headers as specified by RFC 2047,
+and, additionally, the encoding of MIME parameters as specified in RFC 2231.
.PP
-If you specify the name of the composition file as \*(lq-\*(rq,
-then
+If you specify the name of the composition file as \*(lq-\*(rq, then
.B mhbuild
-will accept the composition draft on the standard
-input.
+will accept the composition draft on the standard input.
If the translation of this input is successful,
.B mhbuild
will output the new MIME message to the standard output.
-This argument
-must be the last argument on the command line.
+This argument must be the last argument on the command line.
.PP
-Otherwise if the file argument to
+Otherwise, if the file argument to
.B mhbuild
-is the name of a valid
-composition file, and the translation is successful,
+is the name of a valid composition file, and the translation is successful,
.B mhbuild
will replace the original file with the new MIME message.
-It will rename
-the original file to start with the \*(lq,\*(rq character and end with the
-string \*(lq.orig\*(rq, e.g., if you are editing the file \*(lqdraft\*(rq,
-it will be renamed to \*(lq,draft.orig\*(rq.
-This allows you to easily
-recover the
+It will rename the original file to start with the \*(lq,\*(rq character
+and end with the string \*(lq.orig\*(rq, e.g., if you are editing the file
+\*(lqdraft\*(rq, it will be renamed to \*(lq,draft.orig\*(rq.
+This allows you to easily recover the
.B mhbuild
input file.
.SS "Listing the Contents"
.PP
The
.B \-headers
-switch indicates
-that a one-line banner should be displayed above the listing.
+switch indicates that a one-line banner should be displayed above the listing.
The
.B \-realsize
switch tells
.B mhbuild
-to evaluate the \*(lqnative\*(rq
-(decoded) format of each content prior to listing.
-This provides an
-accurate count at the expense of a small delay.
+to evaluate the \*(lqnative\*(rq (decoded) format of each content prior to listing.
+This provides an accurate count at the expense of a small delay.
If the
.B \-verbose
switch
For users who wish to simply attach files to text content,
.B mhbuild
will scan the composition file for \*(lqAttach\*(rq headers.
-An
-\*(lqAttach\*(rq header contains a filename that will be appended to the
-message using normal MIME encapsulation rules.
-One filename is allowed
+An \*(lqAttach\*(rq header contains a filename that will be appended to the
+message using normal MIME encapsulation rules. One filename is allowed
per \*(lqAttach\*(rq header, but multiple \*(lqAttach\*(rq headers are
-allowed ber composition file.
+allowed per composition file.
.PP
These files will be appended after any other MIME content, including any
content specified by
.B mhbuild
-directives (see below).
-See
+directives (see below). See
.IR send (1)
for more details.
.PP
.BI mhbuild-disposition- type
.RE
.PP
-to supply the disposition value.
-The only supported values are
+to supply the disposition value. The only supported values are
\*(lqattachment\*(rq
and
\*(lqinline\*(rq.
.SS "Convert Interface"
The convert interface is a powerful mechanism that supports
replying to MIME messages.
-These placeholders are used in the following
-description:
+These placeholders are used in the following description:
.RS 5
.TP 15
.PD 0
full path of message being replied to
.PD
.RE
-.PP
-.RE
The convert support is based on pseudoheaders of the form
.PP
.RS 5
.RE
.PP
in the draft.
-For each such pseudoheader, mhbuild looks in the
-profile and
+For each such pseudoheader, mhbuild looks in the profile and
.I mhn.defaults
-for this corresponding
+for the corresponding
.I TYPE
-entry to find the
-converter that supports it:
+entry to find the converter that supports it:
.PP
.RS 5
.BI mhbuild-convert- TYPE : \0CONVERTER
.PP
It's a fatal error if no such entry is found for
.IR TYPE .
-An empty
-entry, e.g.,
+An empty entry, e.g.,
.PP
.RS 5
.B mhbuild-convert-text/html:
excludes parts of that
.I TYPE
from the draft.
+.PP
The
.I mhn.defaults
-file
-contains default
+file contains default
.B mhbuild-convert-text/html
and
-.BR mhbuild-convert-text/plain
-entries.
-Profile entries can be used to override corresponding
+.B mhbuild-convert-text/plain
+entries. Profile entries can be used to override corresponding
.I mhn.defaults
-entries, as usual.
+entries, as usual. Text converters should limit text line lengths
+to a maximum of 78 characters, and must limit them to a maximum of 998
+characters, per RFC 5322 Sec.\& 2.1.1.
.PP
For each
.I TYPE
runs
.I CONVERTER ARGSTRING
on the content of the part.
-.PP
Each part in
.I FILE
that has no corresponding TYPE entry in the profile or
.I mhn.defaults
is
-excluded from the draft; the user can include them using mhbuild
-directives as usual.
+excluded from the draft; the user can include them using mhbuild directives.
.PP
.B repl
inserts
.B Nmh-mhbuild-text/html:
and
.B Nmh-mhbuild-text/plain:
-pseudoheaders in every draft.
-The user can prevent insertion of
+pseudoheaders in every draft. The user can prevent insertion of
content parts of either of those types by putting corresponding empty
entries in their profile.
.PP
of a multipart/alternative part is used.
.PP
mhn.defaults.sh selects the text/html-to-text/plain converter at
-install time.
-It includes
+install time. It includes
.B iconv
and
.BR par ,
in the pipeline only if they are found.
.PP
Some content types require the addition of parameters to the
-Content-Type header, such as
-\*(lqmethod=REPLY\*(rq
+Content-Type header, such as \*(lqmethod=REPLY\*(rq
for text/calendar.
.B mhbuild
looks for a Content-Type header, followed
by a blank line, at the beginning of the converter output.
-If one is
-found, it is used for the corresponding part in the reply draft.
+If one is found, it is used for the corresponding part in the reply draft.
.PP
The convert interface doesn't support different
.IR ARGSTRING s
.IR TYPE .
That would require associating parts by part number with the
.IR ARGSTRING s
-or converters.
-Instead, that can be done (currently, without using
+or converters. Instead, that can be done (currently, without using
the convert support), with
.B mhbuild
directives as described below, e.g.,
#text/html; charset=utf-8 *8bit | mhstore -noverbose -part 42.7 -outfile - | w3m -dump -cols 64 -T text/html -O utf-8
.RE
.PP
-The only way to mix
-convert
-pseudoheaders and
+The only way to mix convert pseudoheaders and
.B mhbuild
directives is to insert the directives before
.B mhbuild
program is installed on your system, it will be set by default
(in
.IR mhn.defaults )
-to filter the converter output.
-It helps to
-set the
-PARINIT
-environment variable, as described in its man page.
+to filter the converter output. It helps to set the PARINIT
+environment variable, as described in
+.IR par (1).
.TP 5
2)
Add this line to your profile:
.IP "" 10
mhbuild-next: $EDITOR
.IP "" 5
-assuming that your EDTIOR environment variable is set; if not, replace
-EDITOR with the name of your editor.
-Without that profile entry, a
+assuming that your EDITOR environment variable is set; if not, replace
+EDITOR with the name of your editor. Without that profile entry, a
response of \*(lqe[dit]\*(rq at the What now? prompt will require
specification of your editor if an
.B \-editor mhbuild
switch is used.
-.RE
.TP 5
3)
If using
source the Bourne-shell compatible functions in
.IR %docdir%/contrib/replaliases .
.br
-That script also sets the
-PARINIT
-environment variable if it was not set.
-.RE
+That script also sets the PARINIT environment variable if it was not set.
.SS "Translating the Composition File"
.B mhbuild
-is essentially a filter to aid in the composition of MIME
-messages.
+is essentially a filter to aid in the composition of MIME messages.
.B mhbuild
will convert an
.B mhbuild
-\*(lqcomposition file\*(rq
-into a valid MIME message.
-A
+\*(lqcomposition file\*(rq into a valid MIME message.
+An
.B mhbuild
-\*(lqcomposition file\*(rq
-is just a file containing plain text that is interspersed
-with various
+\*(lqcomposition file\*(rq is just a file containing plain text that is
+interspersed with various
.B mhbuild
-directives.
-When this file is processed
-by
+directives. When this file is processed by
.BR mhbuild ,
-the various directives will be expanded to the
-appropriate content, and will be encoded according to the MIME standards.
+the various directives will be expanded to the appropriate content, and
+will be encoded according to the MIME standards.
The resulting MIME message can then be sent by electronic mail.
.PP
The formal syntax for a
.B mhbuild
-composition file is defined at the
-end of this document, but the ideas behind this format are not complex.
-Basically, the body contains one or more contents.
-A content consists of
+composition file is defined at the end of this document, but the ideas
+behind this format are not complex.
+Basically, the body contains one or more contents. A content consists of
either a directive, indicated with a \*(lq#\*(rq as the first character
of a line; or, plaintext (one or more lines of text).
-The continuation
-character, \*(lq\\\*(lq, may be used to enter a single directive on more
-than one line, e.g.,
+The continuation character, \*(lq\\\*(lq, may be used to enter a single
+directive on more than one line, e.g.,
.PP
.RS 5
.nf
.B \-directives
switch allows control over whether mhbuild will honor any of the
\*(lq#\*(rq-directives.
-This can also be affected with the #on or
-#off directives, and #pop, which restores the state of processing to
-that preceding the most recent #on or #off.
-(The #on, #off, and #pop
-directives are always honored, of course.) This allows inclusion of
-plain text which looks like mhbuild directives, without causing
-errors:
+This can also be affected with the #on or #off directives, and #pop,
+which restores the state of processing to that preceding the most recent
+#on or #off. (The #on, #off, and #pop directives are always honored,
+of course.) This allows inclusion of plain text which looks like mhbuild
+directives, without causing errors:
.PP
.RS 5
.nf
#off
#include <stdio.h>
-printf("Hello, World!");
+puts("hello, world!");
#pop
.fi
.RE
Currently the stack depth for the #on/off/pop directives is 32.
.PP
The \*(lqtype\*(rq directive is used to directly specify the type and
-subtype of a content.
-You may only specify discrete types in this manner
+subtype of a content. You may only specify discrete types in this manner
(can't specify the types multipart or message with this directive).
You may optionally specify the name of a file containing the contents
in \*(lqnative\*(rq (decoded) format.
-If this filename starts with the
-\*(lq|\*(rq character, then it represents a command to execute whose
-output is captured accordingly.
+If this filename starts with the \*(lq|\*(rq character, then it represents
+a command to execute whose output is captured accordingly.
For example,
.PP
.RS 5
This is accomplished by consulting a composition string, and executing
it under
.BR /bin/sh ,
-with the standard output set to the content.
-If the
+with the standard output set to the content. If the
.B \-verbose
switch is given,
.B mhbuild
.RE
.PP
to determine the command to use to compose the content.
-If this isn't
-found,
+If this isn't found,
.B mhbuild
will look for an entry of the form:
.PP
.BI mhbuild-compose- type
.RE
.PP
-to determine the composition command.
-If this isn't found,
+to determine the composition command. If this isn't found,
.B mhbuild
will complain.
.PP
Because commands like these will vary, depending on the display
environment used for login, composition strings for different
contents should probably be put in the file specified by the
-MHBUILD
-environment variable, instead of directly in your
+MHBUILD environment variable, instead of directly in your
user profile.
.PP
The \*(lqexternal-type\*(rq directives are used to provide a MIME
reference to a content, rather than enclosing the contents itself
(for instance, by specifying an ftp site).
-Hence, instead of
-providing a filename as with the type directives, external-parameters
-are supplied.
-These look like regular parameters, so they must be
-separated accordingly.
+Hence, instead of providing a filename as with the type directives,
+external-parameters are supplied.
+These look like regular parameters, so they must be separated accordingly.
For example,
.PP
.RS 5
.fi
.RE
.PP
-A mimimum \*(lqexternal\-type\*(rq directive for the
+A minimum \*(lqexternal\-type\*(rq directive for the
.B url
-.I access\-type
+.I access-type
would be as follows:
.PP
.RS 3
Any long URLs will be wrapped according to RFC 2231 rules.
.PP
The \*(lqmessage\*(rq directive (#forw) is used to specify a message or
-group of messages to include.
-You may optionally specify the name of
+group of messages to include. You may optionally specify the name of
the folder and which messages are to be forwarded.
-If a folder is not
-given, it defaults to the current folder.
-Similarly, if a message is not
-given, it defaults to the current message.
-Hence, the message directive
-is similar to the
+If a folder is not given, it defaults to the current folder.
+Similarly, if a message is not given, it defaults to the current message.
+Hence, the message directive is similar to the
.B forw
-command, except that the former uses
-the MIME rules for encapsulation rather than those specified in RFC 934.
+command, except that the former uses the MIME rules for encapsulation
+rather than those specified in RFC 934.
For example,
.PP
.RS 5
.PP
If you include a single message, it will be included directly as a content
of type \*(lqmessage/rfc822\*(rq.
-If you include more than one message,
-then
+If you include more than one message, then
.B mhbuild
will add a content of type \*(lqmultipart/digest\*(rq
and include each message as a subpart of this content.
If you are using this directive to include more than one message, you
may use the
.B \-rfc934mode
-switch.
-This switch will indicate that
+switch. This switch will indicate that
.B mhbuild
-should attempt to utilize the MIME encapsulation rules
-in such a way that the \*(lqmultipart/digest\*(rq that is created
-is (mostly) compatible with the encapsulation specified in RFC 934.
+should attempt to utilize the MIME encapsulation rules in such a way
+that the \*(lqmultipart/digest\*(rq that is created is (mostly) compatible
+with the encapsulation specified in RFC 934.
If given, then RFC 934 compliant user-agents should be able to burst the
message on reception\0--\0providing that the messages being encapsulated
do not contain encapsulated messages themselves.
-The drawback of this
-approach is that the encapsulations are generated by placing an extra
-newline at the end of the body of each message.
+The drawback of this approach is that the encapsulations are generated by
+placing an extra newline at the end of the body of each message.
.PP
The \*(lqbegin\*(rq directive is used to create a multipart content.
When using the \*(lqbegin\*(rq directive, you must specify at least one
.PP
If you use multiple directives in a composition draft,
.B mhbuild
-will
-automatically encapsulate them inside a multipart content.
-Therefore the
-\*(lqbegin\*(rq directive is only necessary if you wish to use nested
-multiparts, or create a multipart message containing only one part.
+will automatically encapsulate them inside a multipart content.
+Therefore the \*(lqbegin\*(rq directive is only necessary if you wish to
+use nested multiparts, or create a multipart message containing only one part.
.PP
For all of these directives, the user may include a brief description
of the content between the \*(lq[\*(rq character and the \*(lq]\*(rq
character.
-This description will be copied into the
-\*(lqContent-Description\*(rq header when the directive is processed.
+This description will be copied into the \*(lqContent-Description\*(rq header
+when the directive is processed.
.PP
.RS 5
.nf
If a disposition string is provided that does not contain a filename
parameter, and a filename is provided in the directive, it will be
added to the \*(lqContent-Disposition\*(rq header.
-For example, the
-following directive:
+For example, the following directive:
.PP
.RS 5
.nf
will generate a unique \*(lqContent-ID:\*(rq for each directive,
corresponding to each message part; however, the user may override
this by defining the ID using the \*(lq<\*(rq and \*(lq>\*(rq
-characters.
-The
+characters. The
.B \-nocontentid
switch suppresses creation of all \*(lqContent-ID:\*(rq headers,
even in the top level of the message.
However, you can override that in an
.B mhbuild
directive by specifying \*(lq*\*(rq and the encoding.
-Acceptable encoding
-values are \*(lq8bit\*(rq, \*(lqqp\*(rq (for quoted\-printable), and
-\*(lqb64\*(rq (for base64 encoding).
-It should be noted that undesired
-results may occur if 8bit or quoted\-printable is selected for binary
-content, due to the translation between Unix line endings and the line
-endings use by the mail transport system.
+Acceptable encoding values are \*(lq8bit\*(rq, \*(lqqp\*(rq
+(for quoted-printable), and \*(lqb64\*(rq (for base64 encoding).
+It should be noted that undesired results may occur if 8bit or quoted-printable
+is selected for binary content, due to the translation between Unix line endings
+and the line endings use by the mail transport system.
.PP
In addition to the various directives, plaintext can be present.
Plaintext is gathered, until a directive is found or the draft is
exhausted, and this is made to form a text content.
-If the plaintext
-must contain a \*(lq#\*(rq at the beginning of a line, simply double it,
+If the plaintext must contain a \*(lq#\*(rq at the beginning of a line,
+simply double it,
e.g.,
.PP
.RS 5
.RE
.PP
then this will be used to describe the plaintext content.
-You MUST follow this line with a blank line before starting
-your text.
+You MUST follow this line with a blank line before starting your text.
.PP
By default, plaintext is captured as a text/plain content.
-You can
-override this by starting the plaintext with \*(lq#<\*(rq followed by
-a content-type specification.
-For example, e.g.,
+You can override this by starting the plaintext with \*(lq#<\*(rq followed
+by a content-type specification. For example, e.g.,
.PP
.RS 5
.nf
#<text/plain; charset=iso-8859-5
.RE
.PP
-If a text content contains any 8\-bit characters (characters with the
+If a text content contains any 8-bit characters (characters with the
high bit set) and the character set is not specified as above, then
.B mhbuild
-will assume the character set is of the type given by the
-standard
+will assume the character set is of the type given by the standard
.IR locale (1)
environment variables.
-If these environment variables are not
-set, then the character set will be labeled as \*(lqx-unknown\*(rq.
+If these environment variables are not set, then the character set
+will be labeled as \*(lqx-unknown\*(rq.
.PP
-If a text content contains only 7\-bit characters and the character set
+If a text content contains only 7-bit characters and the character set
is not specified as above, then the character set will be labeled as
\*(lqus-ascii\*(rq.
.PP
-By default text content with the high bit set is encoded with a 8bit
-Content\-Transfer\-Encoding.
-If the text has lines longer than the value
-of
+By default text content with the high bit set is encoded with an 8-bit
+Content-Transfer-Encoding.
+If the text has lines longer than the value of
.B \-maxunencoded
-(which defaults to 78) then the text is encoded using the quoted\-printable
+(which defaults to 78) then the text is encoded using the quoted-printable
encoding.
.PP
The
.B \-headerencoding
switch will indicate which algorithm to use when encoding any message headers
-that contain 8\-bit characters.
+that contain 8-bit characters.
The valid arguments are
.I base64
-for based\-64 encoding,
+for base-64 encoding,
.I quoted
-for quoted\-printable encoding, and
-.I utf-8
+for quoted-printable encoding, and
+.I utf\-8
which requires that all 8-bit header field bodies be encoded as UTF-8
-(RFC 6530) and that the SMTP server support SMTPUTF8 (RFC 6531).
+(RFC 6530) and that the message be sent to a SMTP server that supports
+SMTPUTF8 (RFC 6531).
The
.B \-autoheaderencoding
-switch will instruct
+switch instructs
.B mhbuild
-to automatically pick the algorithm that results in a shorter encoded string.
+to automatically pick the encoding, either base64 or quoted-printable,
+that results in a shorter encoded string.
.PP
-Putting this all together,
-here is an example of a more complicated message draft.
-The
-following draft will expand into a multipart/mixed message
-containing five parts:
+Putting this all together, here is an example of a more complex message draft,
+which will expand into a multipart/mixed message containing five parts:
.PP
.RS 5
.nf
.B \-check
switch, then it will also associate an integrity check with each
\*(lqleaf\*(rq content.
-This will add a Content-MD5 header field to
-the content, along with the md5 sum of the unencoded contents, per RFC
-1864.
-This may be used by the receiver of the message to verify that
-the contents of the message were not changed in transport.
+This will add a Content-MD5 header field to the content, along with the md5
+sum of the unencoded contents, per RFC 1864.
+This may be used by the receiver of the message to verify that the contents
+of the message were not changed in transport.
.SS "Transfer Encodings"
After
.B mhbuild
-constructs the new MIME message by parsing directives,
-including files, etc., it scans the contents of the message to determine
-which transfer encoding to use.
-It will check for 8bit data, long lines,
-spaces at the end of lines, and clashes with multipart boundaries.
-It will
-then choose a transfer encoding appropriate for each content type.
+constructs the new MIME message by parsing directives, including files, etc.,
+it scans the contents of the message to determine which transfer encoding to use.
+It will check for 8-bit data, long lines, spaces at the end of lines, and
+clashes with multipart boundaries.
+It will then choose a transfer encoding appropriate for each content type.
.PP
If an integrity check is being associated with each content by using
the
switch, then
.B mhbuild
will encode each content with
-a transfer encoding, even it the content contains only 7\-bit data.
-This
-is to increase the likelihood that the content is not changed while in
+a transfer encoding, even if the content contains only 7-bit data.
+This is to increase the likelihood that the content is not changed while in
transport.
.SS "Invoking mhbuild"
Typically,
is invoked by the
.B whatnow
program.
-This
-command will expect the body of the draft to be formatted as an
+This command will expect the body of the draft to be formatted as an
.B mhbuild
composition file.
-Once you have composed this input file
-using a command such as
+Once you have composed this input file using a command such as
.BR comp ,
-.BR repl ,
-or
.BR forw ,
+or
+.BR repl ,
you invoke
.B mhbuild
at the \*(lqWhat now\*(rq prompt with
.PP
Normally it is an error to invoke
.B mhbuild
-on file that already in MIME format.
+on a file that is already in MIME format.
The
.B \-auto
switch will cause
.SS "User Environment"
Because the environment in which
.B mhbuild
-operates may vary for a
-user,
+operates may vary for a user,
.B mhbuild
-will look for the environment variable
-MHBUILD .
+will look for the environment variable MHBUILD.
If present, this specifies the name of an additional user profile which
should be read.
-Hence, when a user logs in on a particular machine,
-this environment variable should be set to refer to a file containing
-definitions useful for that machine.
+Hence, when a user logs in on a particular machine, this environment
+variable should be set to refer to a file containing definitions useful
+on that machine.
.PP
Finally,
.B mhbuild
[ "<" id ">" ]
[ "[" description "]" ]
[ "{" disposition "}" ]
- [ "*8bit" | "*qp" | "*b64" ]
+ [ "*8bit" | "*qp" | "*b64" ]
[ filename ]
EOL
[ "<" id ">" ]
[ "[" description "]" ]
[ "{" disposition "}" ]
- [ "*8bit" | "*qp" | "*b64" ]
+ [ "*8bit" | "*qp" | "*b64" ]
external-parameters
EOL
[ "(" comment ")" ]
[ "[" description "]" ]
[ "{" disposition "}" ]
- [ "*8bit" | "*qp" | "*b64" ]
+ [ "*8bit" | "*qp" | "*b64" ]
EOL
1*line
[ "#" EOL ]
.B mhbuild
looks for additional user profile files and
.I mhn.defaults
-in multiple
-locations: absolute pathnames are accessed directly, tilde expansion
-is done on usernames, and files are searched for in the user's
+in multiple locations: absolute pathnames are accessed directly, tilde
+expansion is done on usernames, and files are searched for in the user's
.I Mail
directory as specified in their profile.
If not found there, the directory
.PP
.PD 0
.TP 20
-$HOME/\&.mh\(ruprofile
+$HOME/.mh_profile
The user's profile.
.TP
$MHBUILD
.I "Multipurpose Internet Mail Extensions (MIME) Part Three: Message Header Extensions for Non-ASCII Text"
(RFC 2047)
.PP
+.I "Internet Message Format"
+(RFC 5322)
+.PP
.I "MIME Parameter Value and Encoded Word Extensions: Character Sets, Languages, and Continuations"
(RFC 2231)
.PP