2010年9月15日 — flock() allows you to perform a simple reader/writer model which can be used on virtually every platform (including most Unix derivatives ...
2020年1月11日 — It's documented that flock is not supported on NFS (but not how it will respond to a flock operation), and other mechanisms I've read about, ...
This means that if the file lock is not available, flock() will return immediately with false rather than hang around waiting for a lock to become available.
2015年7月8日 — By default, this function will block until the requested lock is acquired; this may be controlled with the LOCK_NB option documented below. PHP ...
* when the flock is blocked from acquiring a lock. With LOCK_NB. * the flock returns immediately instead of waiting indefinitely. *. * @param resource ...
2016年12月16日 — The downside is that the flock() call waits until any previous lock has been released. This is not practical to warn a user of concurrent ...
sleep(5); // wait for 5 seconds if ($file->flock(LOCK_EX)) // do an exclusive lock $file->fwrite(Write something here-n); $file->flock(LOCK_UN); ...