MIME::QuotedPrint - Encoding and decoding of quoted-printable strings

NAME

MIME::QuotedPrint - Encoding and decoding of quoted-printable strings

SYNOPSIS

 use MIME::QuotedPrint;
 $encoded = encode_qp($decoded);
 $decoded = decode_qp($encoded);

DESCRIPTION

This module provides functions to encode and decode strings into and from the quoted-printable encoding specified in RFC 2045 - MIME (Multipurpose Internet Mail Extensions). The quoted-printable encoding is intended to represent data that largely consists of bytes that correspond to printable characters in the ASCII character set. Each non-printable character (as defined by English Americans) is represented by a triplet consisting of the character ``='' followed by two hexadecimal digits.

The following functions are provided:

encode_qp($str)
encode_qp($str, $eol)
encode_qp($str, $eol, $binmode)
This function returns an encoded version of the string ($str) given as argument.

The second argument ($eol) is the line-ending sequence to use. It is optional and defaults to ``\n''. Every occurrence of ``\n'' is replaced with this string, and it is also used for additional ``soft line breaks'' to ensure that no line end up longer than 76 characters. Pass it as ``\015\012'' to produce data suitable for external consumption. The string ``\r\n'' produces the same result on many platforms, but not all.

The third argument ($binmode) will select binary mode if passed as a TRUE value. In binary mode ``\n'' will be encoded in the same way as any other non-printable character. This ensures that a decoder will end up with exactly the same string whatever line ending sequence it uses. In general it is preferable to use the base64 encoding for binary data; see the MIME::Base64 manpage.

An $eol of ``'' (the empty string) is special. In this case, no ``soft line breaks'' are introduced and binary mode is effectively enabled so that any ``\n'' in the original data is encoded as well.

decode_qp($str);
This function returns the plain text version of the string given as argument. The lines of the result are ``\n'' terminated, even if the $str argument contains ``\r\n'' terminated lines.

If you prefer not to import these routines into your namespace, you can call them as:

  use MIME::QuotedPrint ();
  $encoded = MIME::QuotedPrint::encode($decoded);
  $decoded = MIME::QuotedPrint::decode($encoded);

Perl v5.8 and better allow extended Unicode characters in strings. Such strings cannot be encoded directly, as the quoted-printable encoding is only defined for single-byte characters. The solution is to use the Encode module to select the byte encoding you want. For example:

    use MIME::QuotedPrint qw(encode_qp);
    use Encode qw(encode);
    $encoded = encode_qp(encode("UTF-8", "\x{FFFF}\n"));
    print $encoded;

COPYRIGHT

Copyright 1995-1997,2002-2004 Gisle Aas.

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

SEE ALSO

the MIME::Base64 manpage

 MIME::QuotedPrint - Encoding and decoding of quoted-printable strings