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PHP sleep() Function

< PHP Misc Reference

Example

Delay execution of the current script for 5 seconds:

<?php
echo date('h:i:s') . "<br>";

//sleep for 5 seconds
sleep(5);

//start again
echo date('h:i:s');
?>
Run example »

Definition and Usage

The sleep() function delays execution of the current script for a specified number of seconds.

Note: This function throws an error if the specified number of seconds is negative.


Syntax

sleep(seconds)

Parameter Description
seconds Required. Specifies the number of seconds to delay the script

Technical Details

Return Value: Returns 0 on success, or FALSE on error.

This function returns a non-zero value if the call was interrupted by a signal. On Windows, this value will always be 192, which is the value of the WAIT_IO_COMPLETION constant within the Windows API. On other platforms, the return value will be the number of seconds left to sleep.
PHP Version: 4+
Changelog: Before PHP 5.3.4, this function always returns NULL when sleep has occurred on Windows.

< PHP Misc Reference