usleep
PHP function
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(PHP 4, PHP 5, PHP 7, PHP 8)
Delay execution in microseconds
Description
usleep(int $microseconds): void
Delays program execution for the given number of microseconds.
Parameters
microsecondsHalt time in microseconds. A microsecond is one millionth of a second.
NoteValues larger than
1000000(i.e. sleeping for more than a second) may not be supported by the operating system. Usesleep()instead.NoteThe sleep may be lengthened slightly (i.e. may be longer than
microseconds) by any system activity or by the time spent processing the call or by the granularity of system timers.
Return Values
Void
Examples
usleep() example
php
<?php
// Current time
echo (new DateTime('now'))->format('H:i:s.v'), "\n";
// wait for 2 milliseconds
usleep(2000);
// back!
echo (new DateTime('now'))->format('H:i:s.v'), "\n";
// wait for 30 milliseconds
usleep(30000);
// back again!
echo (new DateTime('now'))->format('H:i:s.v'), "\n";
?>The above example will output:
output
11:13:28.005
11:13:28.007
11:13:28.037