程式設計@筆記

延遲執行當前腳本直到 20 秒：

<?php
// wake up ten seconds from now
time_sleep_until(time()+20);
?>

<?php

//returns false and generates a warning
var_dump(time_sleep_until(time()-1));

// may only work on faster computers, will sleep up to 0.2 seconds
var_dump(time_sleep_until(microtime(true)+0.2));

?>