microtime
microtime
(PHP 4, PHP 5, PHP 7)
microtime — Return current Unix timestamp with microseconds
Description
mixed microtime ([ bool $get_as_float = false ] )
microtime() returns the current Unix timestamp with microseconds. This function is only available on operating systems that support the gettimeofday() system call.
Parameters
Return Values
By default, microtime() returns a string in the form "msec sec", where sec is the number of seconds since the Unix epoch (0:00:00 January 1,1970 GMT), and msec measures microseconds that have elapsed since sec and is also expressed in seconds.
If get_as_float is set to TRUE, then microtime() returns a float, which represents the current time in seconds since the Unix epoch accurate to the nearest microsecond.
Examples
Example #1 Timing script execution with microtime()
<?php
/**
* Simple function to replicate PHP 5 behaviour
*/
function microtime_float()
{
list($usec, $sec) = explode(" ", microtime());
return ((float)$usec + (float)$sec);
}
$time_start = microtime_float();
// Sleep for a while
usleep(100);
$time_end = microtime_float();
$time = $time_end - $time_start;
echo "Did nothing in $time seconds\n";
?> Example #2 Timing script execution in PHP 5
<?php $time_start = microtime(true); // Sleep for a while usleep(100); $time_end = microtime(true); $time = $time_end - $time_start; echo "Did nothing in $time seconds\n"; ?>
Example #3 microtime() and REQUEST_TIME_FLOAT (as of PHP 5.4.0)
<?php // Randomize sleeping time usleep(mt_rand(100, 10000)); // As of PHP 5.4.0, REQUEST_TIME_FLOAT is available in the $_SERVER superglobal array. // It contains the timestamp of the start of the request with microsecond precision. $time = microtime(true) - $_SERVER["REQUEST_TIME_FLOAT"]; echo "Did nothing in $time seconds\n"; ?>
See Also
- time() - Return current Unix timestamp
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Licensed under the Creative Commons Attribution License v3.0 or later.
https://secure.php.net/manual/en/function.microtime.php
