Hướng dẫn usleep vs sleep php

Can any body explain me what is the difference among sleep[] and usleep[] in PHP.

I have directed to use following scripts to do chat application for long pulling but in this script I am getting same effect using usleep[25000]; or without usleep[25000];

page1.php

var lpOnComplete = function[response] {
    console.log[response];
    // do more processing
    lpStart[];
};

var lpStart = function[] {
    $.post['page2.php', {}, lpOnComplete, 'json'];
};

$[document].ready[lpStart];

page2.php

Ian Gregory

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asked Oct 24, 2013 at 5:26

2

The argument to sleep is seconds, the argument to usleep is microseconds. Other than that, I think they're identical.

sleep[$n] == usleep[$n * 1000000]

usleep[25000] only sleeps for 0.025 seconds.

answered Oct 24, 2013 at 5:30

BarmarBarmar

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4

sleep[] allows your code to sleep in seconds.

• sleep[5]; // sleeps for 5 seconds

usleep[] allows your code with respect to microseconds.

• usleep[2500000]; // sleeps for 2.5 seconds

COil

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answered Oct 24, 2013 at 6:29

AshwinAshwin

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usleep[] is used to delay execution in "microseconds" while sleep[] is used to delay execution in seconds. So usleep[25000] is 0.025 seconds.

Is there any difference between the two?

Zo Has

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answered Oct 24, 2013 at 5:37

shahpranafshahpranaf

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One other difference is sleep returns 0 on success, false on error. usleep doesn't return anything.

answered Sep 18, 2017 at 10:35

2

Simply

usleep uses CPU Cycles while sleep does not.

sleep takes seconds as argument

while usleep takes microseconds as argument

answered Jun 11, 2019 at 11:59

Dev MateeDev Matee

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