microtime
    (PHP 3, PHP 4 )
microtime -- 
     Return current UNIX timestamp with microseconds
Description
string 
microtime ( void)
     Returns the string "msec sec" where sec is the current time
     measured in the number of seconds since the Unix Epoch (0:00:00
     January 1, 1970 GMT), and msec is the microseconds part. This
     function is only available on operating systems that support the
     gettimeofday() system call.
    
     Both portions of the string are returned in units of seconds.
     
| Example 1. microtime() example | function getmicrotime(){ 
    list($usec, $sec) = explode(" ",microtime()); 
    return ((float)$usec + (float)$sec); 
    } 
$time_start = getmicrotime();
    
for ($i=0; $i < 1000; $i++){
    //do nothing, 1000 times
    }
$time_end = getmicrotime();
$time = $time_end - $time_start;
echo "Did nothing in $time seconds"; | 
 | 
    
     See also time().