Cette extension est EXPERIMENTALE. Le comportement de cette extension, les noms de ses fonctions, et toute la documentation autour de cette extension peut changer sans préavis dans une prochaine version de PHP. Cette extension doit être utilisée à vos risques et périls.
This extension allows the loading of shared libraries (.DLL or .so), calling of C functions and accessing of C data structures in pure PHP, without having to have deep knowledge of the Zend extension API, and without having to learn a third “intermediate” language. The public API is implemented as a single class FFI with several static methods (some of them may be called dynamically), and overloaded object methods, which perform the actual interaction with C data.
FFI is dangerous, since it allows to interface with the system on a very low level. The FFI extension should only be used by developers having a working knowledge of C and the used C APIs. To minimize the risk, the FFI API usage may be restricted with the ffi.enable php.ini directive.
The FFI extension does not render the classic PHP extension API obsolete; it is merely provided for ad-hoc interfacing with C functions and data structures.
Currently, accessing FFI data structures is significantly (about 2 times) slower than accessing native PHP arrays and objects. Therefore, it makes no sense to use the FFI extension for speed; however, it may make sense to use it to reduce memory consumption.