note 119766 added to function.usleep

usleep() only supports 32-bit signed integers. This means it can only sleep for 2^31 microseconds. (about 35 minutes). It does not emit an error or warning if the number is too large. It simply wraps the int around. This causes unexpected behavior. Attempting to sleep for 24 hours causes the script to sleep for about 8.34 minutes. ( ((24*3600000000) % (2**31)) / 60000000 ) Tested on PHP 5.3, 5.5, 5.6 and 7.0 on OSX and linux. <?php //Sleep that works: usleep((int) pow(2, 30)); // sleep that does NOT work because wrap-around to negative int: usleep((int) pow(2, 32)); // applies to any power > 32 as well. ---- Server IP: 72.52.91.14 Probable Submitter: 87.48.139.251 ---- Manual Page -- http://php.net/manual/en/function.usleep.php Edit -- https://master.php.net/note/edit/119766 Del: integrated -- https://master.php.net/note/delete/119766/integrated Del: useless -- https://master.php.net/note/delete/119766/useless Del: bad code -- https://master.php.net/note/delete/119766/bad+code Del: spam -- https://master.php.net/note/delete/119766/spam Del: non-english -- https://master.php.net/note/delete/119766/non-english Del: in docs -- https://master.php.net/note/delete/119766/in+docs Del: other reasons-- https://master.php.net/note/delete/119766 Reject -- https://master.php.net/note/reject/119766 Search -- https://master.php.net/manage/user-notes.php