Implements hook_node_presave().
function node_test_node_presave(Node $node) {
if ($node->title == 'testing_node_presave') {
// Sun, 19 Nov 1978 05:00:00 GMT
$node->created = 280299600;
// Drupal 1.0 release.
$node->changed = 979534800;
}
// Determine changes.
if (!empty($node->original) && $node->original->title == 'test_changes') {
if ($node->original->title != $node->title) {
$node->title .= '_presave';
}
}
}