MIME::Decoder::NBit(3pm)

1MIME::Decoder::NBit(3)User Contributed Perl DocumentationMIME::Decoder::NBit(3)
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NAME

6       MIME::Decoder::NBit - encode/decode a "7bit" or "8bit" stream
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SYNOPSIS

9       A generic decoder object; see MIME::Decoder for usage.
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DESCRIPTION

12       This is a MIME::Decoder subclass for the "7bit" and "8bit" content
13       transfer encodings.  These are not "encodings" per se: rather, they are
14       simply assertions of the content of the message.  From RFC-2045 Section
15       6.2.:
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17          Three transformations are currently defined: identity, the "quoted-
18          printable" encoding, and the "base64" encoding.  The domains are
19          "binary", "8bit" and "7bit".
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21          The Content-Transfer-Encoding values "7bit", "8bit", and "binary" all
22          mean that the identity (i.e. NO) encoding transformation has been
23          performed.  As such, they serve simply as indicators of the domain of
24          the body data, and provide useful information about the sort of
25          encoding that might be needed for transmission in a given transport
26          system.
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28       In keeping with this: as of MIME-tools 4.x, this class does no
29       modification of its input when encoding; all it does is attempt to
30       detect violations of the 7bit/8bit assertion, and issue a warning (one
31       per message) if any are found.
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33   Legal 7bit data
34       RFC-2045 Section 2.7 defines legal "7bit" data:
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36          "7bit data" refers to data that is all represented as relatively
37          short lines with 998 octets or less between CRLF line separation
38          sequences [RFC-821].  No octets with decimal values greater than 127
39          are allowed and neither are NULs (octets with decimal value 0).  CR
40          (decimal value 13) and LF (decimal value 10) octets only occur as
41          part of CRLF line separation sequences.
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43   Legal 8bit data
44       RFC-2045 Section 2.8 defines legal "8bit" data:
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46          "8bit data" refers to data that is all represented as relatively
47          short lines with 998 octets or less between CRLF line separation
48          sequences [RFC-821]), but octets with decimal values greater than 127
49          may be used.  As with "7bit data" CR and LF octets only occur as part
50          of CRLF line separation sequences and no NULs are allowed.
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52   How decoding is done
53       The decoder does a line-by-line pass-through from input to output,
54       leaving the data unchanged except that an end-of-line sequence of CRLF
55       is converted to a newline "\n".  Given the line-oriented nature of 7bit
56       and 8bit, this seems relatively sensible.
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58   How encoding is done
59       The encoder does a line-by-line pass-through from input to output, and
60       simply attempts to detect violations of the "7bit"/"8bit" domain.  The
61       default action is to warn once per encoding if violations are detected;
62       the warnings may be silenced with the QUIET configuration of
63       MIME::Tools.
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AUTHOR

69       Eryq (eryq@zeegee.com), ZeeGee Software Inc (http://www.zeegee.com).
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71       All rights reserved.  This program is free software; you can
72       redistribute it and/or modify it under the same terms as Perl itself.
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76perl v5.30.1                      2020-01-30            MIME::Decoder::NBit(3)

NAME

SYNOPSIS

DESCRIPTION

SEE ALSO

AUTHOR