PHP | time_nanosleep( ) Function

The time_nanosleep() function in PHP is an inbuilt function which is used to delay the execution of the current script for a specified number of seconds and nanoseconds.

The time_nanosleep() function accepts seconds and nanoseconds as parameters and returns TRUE on success or FALSE on failure.

If the delay is interrupted by a signal, an associative array is returned with the following components:

1. seconds: It denotes the number of seconds remaining in the delay.
2. nanoseconds: It denotes the number of nanoseconds remaining in the delay.

Syntax:

time_nanosleep(seconds, nanoseconds)

Parameters Used:
The time_nanosleep() function in PHP accepts two parameters.

• seconds : It is a mandatory parameter which specifies the number of seconds.
• nanoseconds : It is a mandatory parameter which specifies the number of nanoseconds.

Return Value: It returns TRUE on success or FALSE on failure.If the delay is interrupted by a signal, an associative array is returned with the remaining seconds and nanoseconds.

Errors And Exceptions:

1. The value of nanoseconds passed as parameter must be less than 1, 000, 000, 000.
2. The value of seconds passed as parameter should be non-negative.

Below programs illustrate the time_nanosleep() function:

Program 1:

<?php
// displaying time
if (time_nanosleep(2, 500000000) === true)
{
   echo "Execution delayed for two and half a second";
}
else
{
   echo "No delay in Execution";
}
?>

Output:

Execution delayed for two and  half a second

Program 2:

<?php
// displaying time
echo date('h:i:s');

// delaying execution of the script for 2 seconds and half a second
time_nanosleep(2, 500000000);

// displaying time again
echo ("\n");
echo date('h:i:s');
?>

Output:

06:45:15
06:45:18

Reference : http://php.net/manual/en/function.time-nanosleep.php