php man page for pcntl_setpriority

PCNTL_SETPRIORITY(3)							 1						      PCNTL_SETPRIORITY(3)

pcntl_setpriority - Change the priority of any process

SYNOPSIS
       bool pcntl_setpriority (int  $priority, [int  $pid = getmypid()], [int  $process_identifier = PRIO_PROCESS])

DESCRIPTION
       pcntl_setpriority(3) sets the priority of $pid.

PARAMETERS
	      o $priority
		-$priority is generally a value in the range -20 to 20. The default priority is 0 while a lower numerical value causes more favor-
		able scheduling. Because priority levels can differ between system types and kernel versions, please see your  system's  setprior-
		ity(2) man page for specific details.

	      o $pid
		- If not specified, the pid of the current process is used.

	      o $process_identifier
		- One of PRIO_PGRP, PRIO_USER or PRIO_PROCESS.

RETURN VALUES
	Returns TRUE on success or FALSE on failure.

SEE ALSO
       pcntl_getpriority(3).

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