echo file_get_contents($_FILES["image"]["tmp_name"] doesn't do anything

echo file_get_contents($_FILES["image"]["tmp_name"] doesn't do anything

I have written the following code. Nothing is written in the web browser
and no error is thrown. Can anyone please help me to identify the problem?
try {
echo file_get_contents($_FILES["image"]["tmp_name"]);
} catch (Exception $e) {
echo 'Caught exception: ', $e->getMessage(), "\n";
}