This method returns TRUE on custom wrappers by default if you don't implement the stream_lock() method inside the wrapper : http://php.net/manual/en/streamwrapper.stream-lock.php
(PHP 5 >= 5.3.0, PHP 7)
stream_supports_lock — Tells whether the stream supports locking.
$stream
)Tells whether the stream supports locking through flock().
stream
The stream to check.
성공 시 TRUE
를, 실패 시 FALSE
를 반환합니다.
This method returns TRUE on custom wrappers by default if you don't implement the stream_lock() method inside the wrapper : http://php.net/manual/en/streamwrapper.stream-lock.php