FAQ 9.18 How do I decode a MIME/BASE64 string?

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9.18: How do I decode a MIME/BASE64 string?

    The MIME-Base64 package (available from CPAN) handles this as well as
    the MIME/QP encoding. Decoding BASE64 becomes as simple as:

        use MIME::Base64;
        $decoded = decode_base64($encoded);

    The MIME-Tools package (available from CPAN) supports extraction with
    decoding of BASE64 encoded attachments and content directly from email

    If the string to decode is short (less than 84 bytes long) a more direct
    approach is to use the unpack() function's "u" format after minor

        tr#A-Za-z0-9+/##cd;                   # remove non-base64 chars
        tr#A-Za-z0-9+/# -_#;                  # convert to uuencoded format
        $len = pack("c", 32 + 0.75*length);   # compute length byte
        print unpack("u", $len . $_);         # uudecode and print


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