root/trunk/spec/binary.dbk

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<article>
  <articleinfo>
    <title>
      Binary Data Language-Independent Type for
      <trademark>YAML</trademark>&nbsp;Version&nbsp;1.1
    </title>

    <subtitle>
      Working Draft 2005-01-18
    </subtitle>

    <authorgroup>
      <author>
        <firstname>Oren</firstname>
        <surname>Ben-Kiki</surname>
        <email>oren@ben-kiki.org</email>
      </author>

      <author>
        <firstname>Clark</firstname>
        <surname>Evans</surname>
        <email>cce+yaml@clarkevans.com</email>
      </author>

      <author>
        <firstname>Brian</firstname>
        <surname>Ingerson</surname>
        <email>ingy@ttul.org</email>
      </author>
    </authorgroup>

    <copyright>
      <year>2001-2005</year>
      <holder>Oren Ben-Kiki<fo>,&nbsp;</fo></holder>
      <holder>Clark Evans<fo>,&nbsp;</fo></holder>
      <holder>Brian Ingerson</holder>
    </copyright>

    <legalnotice>
      This document may be freely copied provided it is not modified.
    </legalnotice>

    <abstract>
      <title>Status</title>

      <para>
       This specification is a draft reflecting consensus reached by members of
       the <ulink
       url="http://lists.sourceforge.net/lists/listinfo/yaml-core">yaml-core
       mailing list</ulink>. Any questions regarding this draft should be
       raised on this list.
      </para>
    </abstract>
  </articleinfo>

  <section>
    <variablelist>
      <varlistentry>
        <term>
          <para>
            URI:
          </para>
        </term>

        <listitem>
          <para>
            <userinput>tag:yaml.org,2002:binary</userinput>
          </para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>
          <para>
            Shorthand:
          </para>
        </term>

        <listitem>
          <para>
            <userinput>!!binary</userinput>
          </para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>
          <para>
            Kind:
          </para>
        </term>

        <listitem>
          <para>
            Scalar.
          </para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>
          <para>
            Canonical:
          </para>
        </term>

        <listitem>
          <para>
            Base64 without white space and line breaks.
          </para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>
          <para>
            Regexp:
          </para>
        </term>

        <listitem>
          <para>
            Base64 including white space and line breaks.
          </para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>
          <para>
            Definition:
          </para>
        </term>

        <listitem>
          <para>
            A sequence of zero or more octets (8 bit values).
          </para>

          <para>
            Binary data is serialized using the base64 format as defined by
            <ulink url="http://www.ietf.org/rfc/rfc2045.txt">RFC2045</ulink>
            (MIME), with the following notes:
          </para>

          <itemizedlist>
            <listitem>
              <para>
                The content is not restricted to lines of 76 characters or
                less.
              </para>
            </listitem>

            <listitem>
              <para>
                Characters other than the base64 alphabet, line breaks and
                white space are considered an error.
              </para>
            </listitem>
          </itemizedlist>

          <para>
            Base64 is the recommended way to store opaque binary data in YAML
            files. Note that many forms of binary data have internal structure
            that may benefit from being represented as YAML nodes (e.g. the
            Java serialization format).
          </para>
        </listitem>
      </varlistentry>
    </variablelist>

    <example>
      <title><userinput>!!binary</userinput> Examples</title>
<programlisting>
canonical: !!binary "\
 R0lGODlhDAAMAIQAAP//9/X17unp5WZmZgAAAOfn515eXvPz7Y6OjuDg4J+fn5\
 OTk6enp56enmlpaWNjY6Ojo4SEhP/++f/++f/++f/++f/++f/++f/++f/++f/+\
 +f/++f/++f/++f/++f/++SH+Dk1hZGUgd2l0aCBHSU1QACwAAAAADAAMAAAFLC\
 AgjoEwnuNAFOhpEMTRiggcz4BNJHrv/zCFcLiwMWYNG84BwwEeECcgggoBADs="
generic: !binary |
 R0lGODlhDAAMAIQAAP//9/X17unp5WZmZgAAAOfn515eXvPz7Y6OjuDg4J+fn5
 OTk6enp56enmlpaWNjY6Ojo4SEhP/++f/++f/++f/++f/++f/++f/++f/++f/+
 +f/++f/++f/++f/++f/++SH+Dk1hZGUgd2l0aCBHSU1QACwAAAAADAAMAAAFLC
 AgjoEwnuNAFOhpEMTRiggcz4BNJHrv/zCFcLiwMWYNG84BwwEeECcgggoBADs=
description:
 The binary value above is a tiny arrow encoded as a gif image.
</programlisting>
    </example>
  </section>
</article>