note 98222 added to function.socket-select

The way the document describes socket_select()'s handling of sockets polled for read is rather obscure. It says that it checks to see if reading would not "block," but the overall description of socket_select() says it checks for a change in blocking status. Unfortunately, these are in conflict. If a socket already has data in the buffer, calling socket_select() on that socket would never return (assuming null timeout), and would block forever. :-( This is because the blocking status wouldn't change. It simply stays "non-blocking" It is important to remember NOT to select() on a socket which may already have data available. An example... <?php //... $socket is already here... $done = false; $n = 0; do{ $tmp = 0; $r = $w = $e = array(); $r = array($socket); socket_select($r,$w,$e,null); $n = socket_recv($socket, $tmp, 1024, 0); //$done = true; //Something determines that we are done reading... }while(!$done); ?> This MAY NOT work... socket_select() is always being called... but we may have data in the input buffer. We need to ensure that the last time we read, nothing was read... (empty buffer) <?php //... $socket is already here... $done = false; $n = 0; do{ $tmp = 0; $r = $w = $e = array(); $r = array($socket); if($n === 0) socket_select($r,$w,$e,null); $n = socket_recv($socket, $tmp, 1024, 0); //$done = true; //Something determines that we are done reading... }while(!$done); ?> ---- Server IP: 69.147.83.197 Probable Submitter: 95.211.2.161 (proxied: 127.0.0.1) ---- Manual Page -- http://www.php.net/manual/en/function.socket-select.php Edit -- https://master.php.net/note/edit/98222 Del: integrated -- https://master.php.net/note/delete/98222/integrated Del: useless -- https://master.php.net/note/delete/98222/useless Del: bad code -- https://master.php.net/note/delete/98222/bad+code Del: spam -- https://master.php.net/note/delete/98222/spam Del: non-english -- https://master.php.net/note/delete/98222/non-english Del: in docs -- https://master.php.net/note/delete/98222/in+docs Del: other reasons-- https://master.php.net/note/delete/98222 Reject -- https://master.php.net/note/reject/98222 Search -- https://master.php.net/manage/user-notes.php