(PHP 5, PHP 7, PHP 8)
streamWrapper::stream_lock — Advisory file locking
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
).
operation
operation
is one of the following:
LOCK_SH
to acquire a shared lock (reader).
LOCK_EX
to acquire an exclusive lock (writer).
LOCK_UN
to release a lock (shared or exclusive).
LOCK_NB
if you don't want
flock() to block while locking.
(not supported on Windows)
成功时返回 true
, 或者在失败时返回 false
。
Emits E_WARNING
if call to this method fails (i.e. not implemented).