hook_nodeapi called multiple times with op='update'

Question

I am using the media_mover module. I added some debug code to media_mover's hook_nodeapi:

function media_mover_api_nodeapi(&$node, $op, $a3 = NULL, $a4 = NULL) {
  dsm ("entering hook_nodeapi.  op=$op");
  switch ($op) {
    ...
    case 'update':
       ...
       break;
  }
}

When the user edits and saves a node, hook_nodeapi is getting called twice with $op='update'. Anyone know why this might be?

If media_mover calls node_save during the process of saving the updated node, might that cause hook_nodeapi to be called multiple times with $op='update'?

(I am using Drupal-6.x)

Answer 1

You are spot on.

If a module calls node_save, nodeapi will be called either with update or insert, depending on what happened.

Answer 2

There is a chance to call hook_node_update multiple times if you use field collection items in your content type. The call times depends on the content in the field collection items