(PHP 8 >= 8.4.0)
pcntl_getcpuaffinity — Get the cpu affinity of a process
pidnull, the current process ID is used.
Returns the cpu affinity mask of the process, 或者在失败时返回 false.
A ValueError is thrown when
pid is an invalid process id
or the cpu mask had failed to be created.
If pid is a process for which the current
user has no allowed permission, a E_WARNING
is emitted.