streamWrapper::stream_lock
(PHP 5, PHP 7)
streamWrapper::stream_lock — Advisory file locking
说明
public streamWrapper::stream_lock
( int
$operation
) : bool
This method is called in response to flock(), when
file_put_contents() (when flags
contains LOCK_EX),
stream_set_blocking() and when closing the stream
(LOCK_UN).
参数
-
operation -
operationis one of the following:-
LOCK_SHto acquire a shared lock (reader). -
LOCK_EXto acquire an exclusive lock (writer). -
LOCK_UNto release a lock (shared or exclusive). -
LOCK_NBif you don't want flock() to block while locking. (not supported on Windows)
-
返回值
成功时返回 TRUE, 或者在失败时返回 FALSE。
错误/异常
Emits E_WARNING if call to this method fails (i.e. not implemented).