path: root/system/doc/tutorial/example.xmlsrc

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<chapter>
  <header>
    <copyright>
      <year>2000</year><year>2015</year>
      <holder>Ericsson AB. All Rights Reserved.</holder>
    </copyright>
    <legalnotice>
      Licensed under the Apache License, Version 2.0 (the "License");
      you may not use this file except in compliance with the License.
      You may obtain a copy of the License at
 
          http://www.apache.org/licenses/LICENSE-2.0

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    </legalnotice>

    <title>Problem Example</title>
    <prepared></prepared>
    <docno></docno>
    <date></date>
    <rev></rev>
    <file>example.xml</file>
  </header>

  <section>
    <title>Description</title>
    <p>A common interoperability situation is when you want to incorporate
      a piece of code, solving a complex problem, in your Erlang
      program. Suppose for example, that you have the following C
      functions that you would like to call from Erlang:</p>
      <codeinclude file="complex.c" tag="" type="none"></codeinclude>
    <p>The functions are deliberately kept as simple as possible, for
      readability reasons.</p>
    <p>From an Erlang perspektive, it is preferable to be able to call
      <c>foo</c> and <c>bar</c> without having to bother about that
      they are C functions:</p>
    <pre>
% Erlang code
...
Res = complex:foo(X),
...</pre>
    <p>Here, the communication with C is hidden in the implementation
      of <c>complex.erl</c>.
      In the following sections, it is shown how this module can be
      implemented using the different interoperability mechanisms.</p>
  </section>
</chapter>