class_datastore - error (just enabled file datastore)

[joshtrav]

I am getting this error 3 times daily in the php error logs:

[01-Dec-2015 10:26:44 America/Chicago] PHP Warning:  copy(XXXX/includes/datastore/datastore_cache.php): failed to open stream: Invalid argument in XXXX\includes\class_datastore.php on line 906

I recently enabled the file option in config.php and have been getting the error since. I have already done chmod 777 on the datastore.php file in the includes/datastore directory. Any ideas on what the cause may be.

When looking at the file I notice it calls atomic_move from line 799

atomic_move(DATASTORE . '/datastore_cache_atomic.php', DATASTORE . '/datastore_cache.php');

This is where I assume the issue arises as there is no datastore_cache_atomic.php in the datastore folder. Should I create said file? I would have assumed if vB needed it, it would have created it to begin with.

Thanks for any help.
vB version 4.2.1