time_nanosleep

    (PHP 5, PHP 7, PHP 8)

    time_nanosleep — Delay for a number of seconds and nanoseconds

    Description

    time_nanosleep(int $seconds, int $nanoseconds): array|bool

    Delays program execution for the given number of seconds and nanoseconds.

    Parameters

    seconds

    Must be a non-negative integer.

    nanoseconds

    Must be a non-negative integer less than 1 billion.

    Note: On Windows, the system may sleep longer that the given number of nanoseconds, depending on the hardware.

    Return Values

    Returns true on success or false on failure.

    If the delay was interrupted by a signal, an associative array will be returned with the components:

    • seconds - number of seconds remaining in the delay
    • nanoseconds - number of nanoseconds remaining in the delay

    Examples

    Example #1 time_nanosleep() example

    <?php
    // Careful! This won't work as expected if an array is returned
    if (time_nanosleep(0, 500000000)) {
    echo     "Slept for half a second.\n";
    }

    // This is better:
    if (time_nanosleep(0, 500000000) === true) {
    echo     "Slept for half a second.\n";
    }

    // And this is the best:
    $nano = time_nanosleep(2, 100000);

    if (    $nano === true) {
    echo     "Slept for 2 seconds, 100 microseconds.\n";
    } elseif (    $nano === false) {
    echo     "Sleeping failed.\n";
    } elseif (    is_array($nano)) {
    $seconds = $nano['seconds'];
    $nanoseconds = $nano['nanoseconds'];
    echo     "Interrupted by a signal.\n";
    echo     "Time remaining: $seconds seconds, $nanoseconds nanoseconds.";
    }
    ?>

    See Also

    Found A Problem?

    Learn How To Improve This Page • Submit a Pull Request • Report a Bug
    ＋add a note

    User Contributed Notes 4 notes

    up
    7
    m at kufi dot net
    19 years ago
    You should take into account, if you use the function replacement down here, the CPU will be in use of 99% for the time of execution...

    (A little bit better in this situation is to let the 'full seconds' go by a normal sleep command (makes the thread sleep!, and uses minimum cpu))

    <?php
    //THIS IS THE FUNCTION WE ARE TALKIN ABOUT
    function timeWait($microtime)
    {
    //optimizations added by me [start]
    //sleep the full seconds
    sleep(intval($microtime));
    //set the microtime to only resleep the last part of the nanos
    $microtime = $microtime - intval($microtime);
    //optimizations added by me [end]

    $timeLimit = $microtime + array_sum(explode(" ",microtime()));
    while(    array_sum(explode(" ",microtime())) < $timeLimit)
    {    /*DO NOTHING*/}
    return(    true);
    }

    //THIS IS HOW WE CAN USE IT
    echo "Process started at " . date("H:i:s") . " and " . current(explode(" ",microtime())) . " nanoseconds.<br>";
    timeWait(5.5); //With this call the system will wait 5 seconds and a half. You can use either integer or float.
    echo "Process completed at " . date("H:i:s") . " and " . current(explode(" ",microtime())) . " nanoseconds.";
    ?>
    up
    6
    anybody (a) emuxperts.net
    18 years ago
    Documentation states that "seconds" must be positive. This is not correct, 0 is possible.

    Rather, "seconds" must be non-negative.
    up
    6
    fantasysportswire at yahoo dot com
    18 years ago
    Just glancing at this - and the note from over a year ago with a implementation for windows.. with 5.0.0 and higher it would be simplier to just do something like......

    <?php

    if (!function_exists('time_nanosleep')) {

    function     time_nanosleep($seconds, $nanoseconds) {

    sleep($seconds);
    usleep(round($nanoseconds/100));

    return     true;

    }

    }

    ?>

    ....off the top of my head - obviously simple enough there should be no mistakes.. but those are the ones that always seem to get ya :( .....
    up
    3
    b dot andrew at shaw dot ca
    16 years ago
    A response to the note below:

    Your function is also useless, as the WinNT 32 kernel only functions at a minimum of about 10+ ms (1,000 us), rendering usleep() useless, because usleep uses the C function which is provided by the system (in this case, kernel32.dll).

    You'll want to use a function that does not rely on the kernel, but rather something made for precise measurement:

    <?php
    function usleep_win( $micro_seconds )
    {
    if ( @    function_exists( "socket_create" ) && @function_exists( "socket_select" ) )
    {
    $false = NULL;
    $socket = array( socket_create( AF_INET, SOCK_RAW, $false ) );
    socket_select( $false, $false, $socket, 0, $micro_seconds );
    return     true;
    }
    else
    {
    return     false;
    }
    }
    ?>

    This function will allow to you sleep for a specified microsecond, although I have measured it to be off by ~5 us.

    Again, most of this depends on the hardware in your system. If you _REALLY_ need to be precise to < 10 us, you shouldn't be using WinNT anyways!
    ＋add a note
    To Top