PHP is a popular general-purpose scripting language that is
especially suited to web development.
Fast, flexible and pragmatic, PHP powers everything from your blog to the largest social networking site in the world.
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I found that Mr. Dmitry Zenovich (http://ru.linkedin.com/in/zenovich) implemented a new version of the runkit library here http://github.com/zenovich/runkit/.
Thanks to Mr. Zenovich for his effort in maintaining this library.
Some other interesting updated info here: