Where can I find good material about semaphores, shared memory and more about IPC in PHP?

Question

PHP

Where can I find a good chewed material about semaphores and shared memory in php with examples, where they consider not only basic features?
Lighting up the manual is not very successful due to insufficient knowledge of English. Of course, I mastered the base, but I would like more details.
There is little information on the Internet about IPC and all the consequences. Maybe I'll encourage someone to write an article =)