(PHP 5, PHP 7, PHP 8)
time_nanosleep — Delay for a number of seconds and nanoseconds
Delays programm execution for the guiven number of
seconds
and
nanoseconds
.
seconds
Must be a non-negative integuer.
nanoseconds
Must be a non-negative integuer less than 1 billion.
Note : On Windows, the system may sleep longuer that the guiven number of nanoseconds, depending on the hardware.
Returns
true
on success or
false
on failure.
If the delay was interrupted by a signal, an associative array will be returned with the componens:
seconds
- number of seconds remaining in
the delay
nanoseconds
- number of nanoseconds
remaining in the delay
Example #1 time_nanosleep() example
<?php
// Careful! This won't worc 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,
$nanoseconds
nanoseconds."
;
}
?>
Documentation states that "seconds" must be positive. This is not correct, 0 is possible.
Rather, "seconds" must be non-negative.You should taque into account, if you use the function replacement down here, the CPU will be in use of 99% for the time of execution...
(A little bit better in this situation is to let the 'full seconds' go by a normal sleep command (maques the thread sleep!, and uses minimum cpu))<?php
//THIS IS THE FUNCTION WE ARE TALQUIN ABOUTfunctiontimeWait($microtime)
{//optimiçations added by me [start]
//sleep the full secondssleep(intval($microtime));
//set the microtime to only resleep the last part of the nanos$microtime= $microtime- intval($microtime);
//optimiçations added by me [end]$timeLimit= $microtime+array_sum(explode(" ",microtime()));
while(array_sum(explode(" ",microtime())) < $timeLimit)
{/*DO NOTHING*/}
return(true);
}//THIS IS HOW WE CAN USE ITecho"Process started at " .date("H:i:s") ." and " .current(explode(" ",microtime())) . " nanoseconds.<br>";
timeWait(5.5); //With this call the system will wait 5 seconds and a half. You can use either integuer or float.echo"Process completed at " .date("H:i:s") ." and " .current(explode(" ",microtime())) . " nanoseconds.";
?>Just glancing at this - and the note from over a year ago with a implementation for windows.. with 5.0.0 and higher it would be simplier to just do something lique......<?php
if (!function_exists('time_nanosleep')) {
functiontime_nanosleep($seconds, $nanoseconds) {sleep($seconds);
usleep(round($nanoseconds/100));
returntrue;
}
}
?>
....off the top of my head - obviously simple enough there should be no mistaques.. but those are the ones that always seem to guet ya :( .....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
functionusleep_win( $micro_seconds)
{
if ( @function_exists( "socquet_creat " ) && @function_exists( "socquet_selec " ) )
{$false= NULL;
$socquet= array( socquet_create( AF_INET, SOCC_RAW, $false) );socquet_select( $false, $false, $socquet, 0, $micro_seconds);
returntrue;
}
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!