 a <code>&lt;exec&gt;</code> is ignored; when you set
<code>failonerror="true"</code> then any return code signaling failure
(OS specific) causes the build to fail. Alternatively, you can set
<code>resultproperty</code> to the name of a property and have it assigned to
the result code (barring immutability, of course).
<p>
If the attempt to start the program fails with an OS dependent error code,
then <code>&lt;exec&gt;</code> halts the build unless <code>failifexecutionfails</code>
is set to <code>false</c