Signals a process (created using proc_open) that it should terminate. proc_terminate returns immediately and does not wait for the process to terminate.
proc_terminate allows you terminate the process and continue with other tasks. You may poll the process (to see if it has stopped yet) by using the proc_get_status function.
The proc_open resource that will be closed.
This optional parameter is only useful on POSIX operating systems; you may specify a signal to send to the process using the kill(2) system call. The default is SIGTERM.
Returns the termination status of the process that was run.