Attaching image files to nodes programmatically in Drupal 7

Question

Is it possible to add an image to a node programmatically?

Answer 1

$node->field_image[LANGUAGE_NONE][0] = (array)$file;

I tried this with a multilingual site. It failed fairly... but horribly. I had to specify the language in question. Simply put, this worked instead:

$node->field_image['en'][0] = (array)$file;

Without it, the attached file was viewable in the 'view' screen but not in the 'edit' screen.