Quoted-printable - Revision history

Jsummers: Change primary category to Transfer Encodings

2014-08-24T22:57:15Z

Change primary category to Transfer Encodings

Dan Tobias at 04:33, 12 December 2012

2012-12-12T04:33:02Z

Halftheisland: v. minor typo fix

2012-12-11T14:07:34Z

v. minor typo fix

Dan Tobias at 13:46, 11 December 2012

2012-12-11T13:46:49Z

Dan Tobias at 13:45, 11 December 2012

2012-12-11T13:45:15Z

Dan Tobias: /* References */

2012-12-11T13:44:57Z

‎References

Dan Tobias: Created page with "{{FormatInfo |subcat=E-Mail, newsgroups, and forums }} ''Quoted-printable''' is one of the two transfer encodings used in MIME e-mail messages to encode binary data entirely ..."

2012-12-11T13:44:48Z

Created page with "{{FormatInfo |subcat=E-Mail, newsgroups, and forums }} ''Quoted-printable''' is one of the two transfer encodings used in MIME e-mail messages to encode binary data entirely ..."

New page

{{FormatInfo
|subcat=E-Mail, newsgroups, and forums
}}

''Quoted-printable''' is one of the two transfer encodings used in MIME e-mail messages to encode binary data entirely in characters of the 7-bit [[ASCII]] range so that it could be safely transmitted even through systems not supporting anything else (which was more of an issue in the 1970s when e-mail protocols were defined than at present). The other encoding is [[Base64]], which is best suited for binary data. Quoted-printable is desigend for data that is mostly ASCII text but may have a few "unsafe" characters needing encoding. It leaves normal "printable" ASCII alone, so that a quoted-printable text file is mostly readable without decoding; only the non-ASCII characters (and a few other special cases) are specially encoded.

The equal sign (=) is used as the "escape" character to indicated encoded sequences. It is followed by two hexadecimal digits (0-9, A-F) which represent the value of an encoded 8-bit byte. Any sequence of bytes can be encoded in this manner, including binary files, but quoted-printable is mostly used for text files (which might be in any number of encodings, such as [[UTF-8]] or [[ISO 8859-1]]).

Normal printable characters (ASCII 33-126 decimal) are represented by themselves, escept for the equal sign (ASCII 61 decimal) which is represented by =3D .

Line breaks are represented by CR+LF (as raw characters). A line break immediately preceded by = (at the end of the previous line) is considered a soft line break, removed in decoding. (Soft line breaks are always inserted to keep the quoted-printable lines no more than 76 characters to avoid problems with transmission through programs that limit line length.) An encoded CR or LF (=0D or =0A) indicates use of those control characters in the original document for a purpose other than normal line breaks (e.g., as part of a binary file).

Spaces and tabs at the end of a line need to be encoded as =20 and =09 respectively, since otherwise, whitespace in such a position is ignored.

== References ==
* [http://en.wikipedia.org/wiki/Quoted-printable Quoted-printable (Wikipedia)
* RFC 1521
* RFC 2045

@@ Line 1: / Line 1: @@
 {{FormatInfo
-|subcat=E-Mail, newsgroups, and forums
+|subcat=Transfer Encodings
 }}
 '''Quoted-printable''' is one of the two transfer encodings used in [[MIME]] e-mail messages to encode binary data entirely in characters of the 7-bit [[ASCII]] range so that it could be safely transmitted even through systems not supporting anything else (which was more of an issue in the 1970s when e-mail protocols were defined than at present). The other encoding is [[Base64]], which is best suited for binary data. Quoted-printable is designed for data that is mostly ASCII text but may have a few "unsafe" characters needing encoding. It leaves normal "printable" ASCII alone, so that a quoted-printable text file is mostly readable without decoding; only the non-ASCII characters (and a few other special cases) are specially encoded.
-'''Quoted-printable''' is one of the two transfer encodings used in [[Mime-type|MIME]] e-mail messages to encode binary data entirely in characters of the 7-bit [[ASCII]] range so that it could be safely transmitted even through systems not supporting anything else (which was more of an issue in the 1970s when e-mail protocols were defined than at present). The other encoding is [[Base64]], which is best suited for binary data. Quoted-printable is designed for data that is mostly ASCII text but may have a few "unsafe" characters needing encoding. It leaves normal "printable" ASCII alone, so that a quoted-printable text file is mostly readable without decoding; only the non-ASCII characters (and a few other special cases) are specially encoded.
 A Quoted-printable-encoded message part is indicated in its MIME headers (following the '''Content-type''' header giving the type of data) with the line:
@@ Line 21: / Line 20: @@
 * RFC 1521
 * RFC 2045

@@ Line 3: / Line 3: @@
 }}
-'''Quoted-printable''' is one of the two transfer encodings used in MIME e-mail messages to encode binary data entirely in characters of the 7-bit [[ASCII]] range so that it could be safely transmitted even through systems not supporting anything else (which was more of an issue in the 1970s when e-mail protocols were defined than at present). The other encoding is [[Base64]], which is best suited for binary data. Quoted-printable is designed for data that is mostly ASCII text but may have a few "unsafe" characters needing encoding. It leaves normal "printable" ASCII alone, so that a quoted-printable text file is mostly readable without decoding; only the non-ASCII characters (and a few other special cases) are specially encoded.
+'''Quoted-printable''' is one of the two transfer encodings used in [[Mime-type|MIME]] e-mail messages to encode binary data entirely in characters of the 7-bit [[ASCII]] range so that it could be safely transmitted even through systems not supporting anything else (which was more of an issue in the 1970s when e-mail protocols were defined than at present). The other encoding is [[Base64]], which is best suited for binary data. Quoted-printable is designed for data that is mostly ASCII text but may have a few "unsafe" characters needing encoding. It leaves normal "printable" ASCII alone, so that a quoted-printable text file is mostly readable without decoding; only the non-ASCII characters (and a few other special cases) are specially encoded.
 A Quoted-printable-encoded message part is indicated in its MIME headers (following the '''Content-type''' header giving the type of data) with the line:

@@ Line 3: / Line 3: @@
 }}
-'''Quoted-printable''' is one of the two transfer encodings used in MIME e-mail messages to encode binary data entirely in characters of the 7-bit [[ASCII]] range so that it could be safely transmitted even through systems not supporting anything else (which was more of an issue in the 1970s when e-mail protocols were defined than at present). The other encoding is [[Base64]], which is best suited for binary data. Quoted-printable is desigend for data that is mostly ASCII text but may have a few "unsafe" characters needing encoding. It leaves normal "printable" ASCII alone, so that a quoted-printable text file is mostly readable without decoding; only the non-ASCII characters (and a few other special cases) are specially encoded.
+'''Quoted-printable''' is one of the two transfer encodings used in MIME e-mail messages to encode binary data entirely in characters of the 7-bit [[ASCII]] range so that it could be safely transmitted even through systems not supporting anything else (which was more of an issue in the 1970s when e-mail protocols were defined than at present). The other encoding is [[Base64]], which is best suited for binary data. Quoted-printable is designed for data that is mostly ASCII text but may have a few "unsafe" characters needing encoding. It leaves normal "printable" ASCII alone, so that a quoted-printable text file is mostly readable without decoding; only the non-ASCII characters (and a few other special cases) are specially encoded.
 A Quoted-printable-encoded message part is indicated in its MIME headers (following the '''Content-type''' header giving the type of data) with the line:

← Older revision		Revision as of 13:46, 11 December 2012
Line 4:		Line 4:

	'''Quoted-printable''' is one of the two transfer encodings used in MIME e-mail messages to encode binary data entirely in characters of the 7-bit [[ASCII]] range so that it could be safely transmitted even through systems not supporting anything else (which was more of an issue in the 1970s when e-mail protocols were defined than at present). The other encoding is [[Base64]], which is best suited for binary data. Quoted-printable is desigend for data that is mostly ASCII text but may have a few "unsafe" characters needing encoding. It leaves normal "printable" ASCII alone, so that a quoted-printable text file is mostly readable without decoding; only the non-ASCII characters (and a few other special cases) are specially encoded.		'''Quoted-printable''' is one of the two transfer encodings used in MIME e-mail messages to encode binary data entirely in characters of the 7-bit [[ASCII]] range so that it could be safely transmitted even through systems not supporting anything else (which was more of an issue in the 1970s when e-mail protocols were defined than at present). The other encoding is [[Base64]], which is best suited for binary data. Quoted-printable is desigend for data that is mostly ASCII text but may have a few "unsafe" characters needing encoding. It leaves normal "printable" ASCII alone, so that a quoted-printable text file is mostly readable without decoding; only the non-ASCII characters (and a few other special cases) are specially encoded.
		+
		+	A Quoted-printable-encoded message part is indicated in its MIME headers (following the '''Content-type''' header giving the type of data) with the line:
		+
		+	Content-Transfer-Encoding: Quoted-Printable

	The equal sign (=) is used as the "escape" character to indicated encoded sequences. It is followed by two hexadecimal digits (0-9, A-F) which represent the value of an encoded 8-bit byte. Any sequence of bytes can be encoded in this manner, including binary files, but quoted-printable is mostly used for text files (which might be in any number of encodings, such as [[UTF-8]] or [[ISO 8859-1]]).		The equal sign (=) is used as the "escape" character to indicated encoded sequences. It is followed by two hexadecimal digits (0-9, A-F) which represent the value of an encoded 8-bit byte. Any sequence of bytes can be encoded in this manner, including binary files, but quoted-printable is mostly used for text files (which might be in any number of encodings, such as [[UTF-8]] or [[ISO 8859-1]]).

@@ Line 14: / Line 14: @@
 == References ==
-* [http://en.wikipedia.org/wiki/Quoted-printable Quoted-printable (Wikipedia)
+* [http://en.wikipedia.org/wiki/Quoted-printable Quoted-printable (Wikipedia)]
 * RFC 1521
 * RFC 2045