check is Process is Alive from PID while handling recycled PID

From what I seen online you call kill method in c++ in order to see if the process is alive. the issue with that is PID's get rycled and the same PID your looking for may not be the same process. I have a program that has two processes that are not children of each other. The only way to communicate with them is IPC. I would like my host process to shutdown when the client process shuts down. In order to do that I have to know when the client's process is no longer alive. In Windows, they have what's called a process handler that will reserve the PID from getting recycled until the process that created the handle is closed. I am wondering how to achieve this for macOS/Linux (POSIX) systems. The problematic code as PID's are reycled.

if (0 == kill(pid, 0))
{
    // Process exists.
}