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<title>Simple Example (libffi: the portable foreign function interface library)</title>

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<span id="Simple-Example-1"></span><h3 class="section">2.2 Simple Example</h3>

<p>Here is a trivial example that calls <code>puts</code> a few times.
</p>
<div class="example">
<pre class="example">#include &lt;stdio.h&gt;
#include &lt;ffi.h&gt;

int main()
{
  ffi_cif cif;
  ffi_type *args[1];
  void *values[1];
  char *s;
  ffi_arg rc;
  
  /* Initialize the argument info vectors */    
  args[0] = &amp;ffi_type_pointer;
  values[0] = &amp;s;
  
  /* Initialize the cif */
  if (ffi_prep_cif(&amp;cif, FFI_DEFAULT_ABI, 1, 
		       &amp;ffi_type_sint, args) == FFI_OK)
    {
      s = &quot;Hello World!&quot;;
      ffi_call(&amp;cif, puts, &amp;rc, values);
      /* rc now holds the result of the call to puts */
      
      /* values holds a pointer to the function's arg, so to 
         call puts() again all we need to do is change the 
         value of s */
      s = &quot;This is cool!&quot;;
      ffi_call(&amp;cif, puts, &amp;rc, values);
    }
  
  return 0;
}
</pre></div>

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