note 118174 added to function.sem-get

For those that encounter strange behavior in using sem_acquire() on resources generated by sem_get(). Have a look at sem_get()'s 4th parameter auto_release. It allows multiple acquisitions through reassignments to resource variables. ./multi.acquire.php <?php class Sem { private $key = null; private $res = null; public function __construct() { $this->key = ftok(".","."); $this->set_res(); $this->acquire(); } public function set_res() { // 4th parameter auto_released is 1 by default $this->res = sem_get($this->key, 1, 0600, 1); } public function acquire() { echo "acquired='".sem_acquire($this->res,true)."'\n"; } } $s = new Sem(); $s->set_res(); $s->acquire(); ?> $ php multi.acquire.php acquired='1' acquired='1' To avoid reacquiring by default set sem_get()'s parameter auto_release to 0 or check if your resource variable is already set, e.g. by using is_null(). ---- Server IP: 72.52.91.14 Probable Submitter: 87.178.177.163 ---- Manual Page -- http://php.net/manual/en/function.sem-get.php Edit -- https://master.php.net/note/edit/118174 Del: integrated -- https://master.php.net/note/delete/118174/integrated Del: useless -- https://master.php.net/note/delete/118174/useless Del: bad code -- https://master.php.net/note/delete/118174/bad+code Del: spam -- https://master.php.net/note/delete/118174/spam Del: non-english -- https://master.php.net/note/delete/118174/non-english Del: in docs -- https://master.php.net/note/delete/118174/in+docs Del: other reasons-- https://master.php.net/note/delete/118174 Reject -- https://master.php.net/note/reject/118174 Search -- https://master.php.net/manage/user-notes.php