Respond to a file being added.
This hook is called after a file has been added to the database. The hook doesn't distinguish between files created as a result of a copy or those created by an upload.
$file: The file that has been added.
Note: this list is generated by pattern matching, so it may include some functions that are not actually implementations of this hook.
function hook_file_insert($file) {
// Add a message to the log, if the file is a jpg
$validate = file_validate_extensions($file, 'jpg');
if (empty($validate)) {
watchdog('file', 'A jpg has been added.');
}
}