|string||The full path and filename of the archive to check|
|string/integer||The name or index of a file to check|
Checks whether the read-only flag is enabled or disabled for the given file and returns
false. If the input archive or file within do not exist,
false will also be returned, as this indicates the archive/file can be written.
This function does not support folders as file inputs.
This will check if a file is read-only before attempting to rename it.