FYI APCu appears to work with CLI PHP and fork()

I always knew that APCu shares RAM across e.g. Apache PHP processes, and that in PHP CLI mode it can be enabled but basically cannot share RAM with other CLI processes. Since Automattic/prefork uses CLI mode to run its service/worker/intern processes then things are potentially bad if the code you are porting to Automattic/prefork relies on APCu. But wait! This example code below shows that APCu shares RAM just fine between fork()ed instances of the same PHP CLI process :-)

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