doc/glossary.ehtml

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  <h1>Glossary</h1>

  <h2>Binary Term Sequence File</h2>

  <p>A BTSF file is a sequence of terms <b>T1, T2, ...</b>
  encoded as follows:</p>

  <table>
    <tr><td>encode_term(T1)</td></tr>
    <tr><td>encode_term(T2)</td></tr>
    <tr><td>...</td></tr>
  </table>
  
  <p>Where:</p>

  <pre>
    encode_term(Term) ->
        Bin = term_to_binary(Term),
	Len = size(Bin),
	&lt;&lt;Len:32/big,Bin/binary>>.
  </pre>

  <p>An individual term <b>T</b> is represented by a length count <b>Len</b>
  <i>(A 32 bit big endian integer)</i> followed by a <b>Len</b>
  byte binary. The binary is made by calling <b>term_to_binary(T)</b>.</p>

  <p>
    Files of encoded binary terms can be read and written extremely
    efficiently using the routines in <b>elib1_fast_read</b>
    and <b>elib1_fast_write</b>.
  </p>

  <p>Library modules like <b>sort_file</b> make use of buffered I/O to
  sort BTSF file very efficiently.</p>
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