note 115381 added to function.curl-multi-select

Even after so many distro releases, in PHP v5.5.9 and libcurl v7.35.0, curl_multi_select still returns -1. The only work around here is to wait and proceed like nothing ever happened. You have to determine the "wait" required here. In my application a very small interval like usleep(1) worked. For example: <?php // While we're still active, execute curl $active = null; do { $mrc = curl_multi_exec($multi, $active); } while ($mrc == CURLM_CALL_MULTI_PERFORM); while ($active && $mrc == CURLM_OK) { // Wait for activity on any curl-connection if (curl_multi_select($multi) == -1) { usleep(1); } // Continue to exec until curl is ready to // give us more data do { $mrc = curl_multi_exec($multi, $active); } while ($mrc == CURLM_CALL_MULTI_PERFORM); } ?> Internally php curl_multi_select uses libcurl curl_multi_fdset function and its libcurl documentation says : http://curl.haxx.se/libcurl/c/curl_multi_fdset.html "When libcurl returns -1 in max_fd, it is because libcurl currently does something that isn't possible for your application to monitor with a socket and unfortunately you can then not know exactly when the current action is completed using select(). When max_fd returns with -1, you need to wait a while and then proceed and call curl_multi_perform anyway. How long to wait? I would suggest 100 milliseconds at least, but you may want to test it out in your own particular conditions to find a suitable value. When doing select(), you should use curl_multi_timeout to figure out how long to wait for action." Untill PHP implements curl_multi_timeout() we have to play with our application and determine the "wait". ---- Server IP: 72.52.91.14 Probable Submitter: 14.141.33.202 ---- Manual Page -- http://php.net/manual/en/function.curl-multi-select.php Edit -- https://master.php.net/note/edit/115381 Del: integrated -- https://master.php.net/note/delete/115381/integrated Del: useless -- https://master.php.net/note/delete/115381/useless Del: bad code -- https://master.php.net/note/delete/115381/bad+code Del: spam -- https://master.php.net/note/delete/115381/spam Del: non-english -- https://master.php.net/note/delete/115381/non-english Del: in docs -- https://master.php.net/note/delete/115381/in+docs Del: other reasons-- https://master.php.net/note/delete/115381 Reject -- https://master.php.net/note/reject/115381 Search -- https://master.php.net/manage/user-notes.php