proc_nice
(PHP 5, PHP 7, PHP 8)
proc_nice — Change the priority of the current process
Description
$priority
): bool
proc_nice() changes the priority of the current
process by the amount specified in priority
. A
positive priority
will lower the priority of the
current process, whereas a negative priority
will raise the priority.
proc_nice() is not related to proc_open() and its associated functions in any way.
Parameters
-
priority
-
The new priority value, the value of this may differ on platforms.
On Unix, a low value, such as
-20
means high priority whereas positive values have a lower priority.For Windows the
priority
parameter has the following meaning:Priority class Possible values High priority priority
< -9
Above normal priority priority
< -4
Normal priority priority
< 5
&priority
> -5
Below normal priority priority
> 5
Idle priority priority
> 9
Return Values
Returns true
on success or false
on failure.
If an error occurs, like the user lacks permission to change the priority,
an error of level E_WARNING
is also generated.
Changelog
Version | Description |
---|---|
7.2.0 | This function is now available on Windows. |
Examples
Example #1 Using proc_nice() to set the process priority to high
<?php
// Highest priority
proc_nice(-20);
?>
Notes
Note: Availability
proc_nice() will only exist if your system has 'nice' capabilities. 'nice' conforms to: SVr4, SVID EXT, AT&T, X/OPEN, BSD 4.3.
Note: Windows only
proc_nice() will change the current process priority, even if PHP was compiled using thread safety.
See Also
- pcntl_setpriority() - Change the priority of any process