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This article is about how PHP uses the flock() function. Xiaobian thinks it is quite practical, so share it with everyone for reference. Let's follow Xiaobian and have a look.

flock();--lightweight advisory file lock

bool flock ( resource $handle , int $operation [, int &$wouldblock ] )//flock() allows the implementation of a simple read/write model that can be used on any platform (including most Unix derivatives and even Windows).

Parameters: handle file system pointer, which is the resource typically created by fopen().

Operation can be one of the following values:

LOCK_SH Acquire shared lock (read program).

LOCK_EX acquires an exclusive lock (program written).

LOCK_UN releases locks (whether shared or exclusive).

LOCK_NB if you don't want flock() to jam when locked (not yet supported on Windows).

Wouldblock: Optional third parameter is set to TRUE if the lock would block (in case of EWOULDBLOCK error code). (Not supported on Windows)

if (flock($fp, LOCK_EX)) { //perform exclusive lock ftruncate($fp, 0); // truncate file fwrite($fp, "Write something here\n"); fflush($fp); // flush output before releasing the lock flock($fp, LOCK_UN); //release lock} else { echo "Couldn't get the lock! ";}fclose($fp); Thank you for reading! About "PHP how to use the flock() function" this article is shared here, I hope the above content can have some help for everyone, so that everyone can learn more knowledge, if you think the article is good, you can share it to let more people see it!

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