​x
 
<!DOCTYPE html>
<html>
<body>
​
<?php
echo(microtime());
​
​
/**
 * 简单的函数，用于模拟 PHP 5 的行为
 */
function microtime_float()
{
    list($usec, $sec) = explode(" ", microtime());
    return ((float)$usec + (float)$sec);
}
​
$time_start = microtime_float();
​
// 休眠一段时间
usleep(100);
​
$time_end = microtime_float();
$time = $time_end - $time_start;
​
echo "在 $time 秒内什么也没做\n";
?>
​
</body>
</html>