PHP: Hypertext Preprocessor (original) (raw)

microtime

(PHP 4, PHP 5, PHP 7, PHP 8)

microtime — Return current Unix timestamp with microseconds

Description

For performance measurements, using hrtime() is recommended.

Parameters

as_float

If used and set to [true](reserved.constants.php#constant.true), microtime() will return afloat instead of a string, as described in the return values section below.

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 as a decimal fraction.

If as_float is set to [true](reserved.constants.php#constant.true), thenmicrotime() 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

`<?php
$time_start = microtime(true);// Sleep for a while
usleep(100);$time_end = microtime(true); time=time = time=time_end - $time_start;

echo

"Did nothing in $time seconds\n";
?>`

Example #2 microtime() and REQUEST_TIME_FLOAT

`<?php
// Randomize sleeping time
usleep(mt_rand(100, 10000));// 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)−time = microtime(true) - time=microtime(true)−_SERVER["REQUEST_TIME_FLOAT"];