note 74829 added to function.flock

Hello, I want to give an example how to lock file with two or more flags (for example reading and writing). IMPORTANT: each locking should be done separately, the correct way of using flock() is: <?php flock($fp, LOCK_EX); flock($fp, LOCK_SH); ?> and NOT like these: <?php flock($fp, LOCK_EX and LOCK_SH); flock($fp, LOCK_EX or LOCK_SH); flock($fp, LOCK_EX + LOCK_SH); ?> Furthermore if someone has not pay attention to function’s description - flock does not lock any file in the right way. The file is still accessible for reading/writing, in other words these functions: file(), file_get_contents() and even fopen($file, ‘r’) will ignore the lock. I think PHP mechanism works something like this: as soon as file lock was successful, the function flock() writes somewhere (in its own “DB” for example) that file handle is locked with some flag and nothing more. It is up to the developer to check if file is locked or not before doing any operations. Hope this post makes clear the flock() function’s working principles. Regards Vitali Simsive ---- Server IP: 69.147.83.197 Probable Submitter: 212.72.146.171 ---- Manual Page -- http://www.php.net/manual/en/function.flock.php Edit -- https://master.php.net/note/edit/74829 Del: integrated -- https://master.php.net/note/delete/74829/integrated Del: useless -- https://master.php.net/note/delete/74829/useless Del: bad code -- https://master.php.net/note/delete/74829/bad+code Del: spam -- https://master.php.net/note/delete/74829/spam Del: non-english -- https://master.php.net/note/delete/74829/non-english Del: in docs -- https://master.php.net/note/delete/74829/in+docs Del: other reasons-- https://master.php.net/note/delete/74829 Reject -- https://master.php.net/note/reject/74829 Search -- https://master.php.net/manage/user-notes.php