Ffi_talk is a project mainly written in RUBY and C, it's free.
slides and example code from pghrb ffi lighting talk
= FFI Talk
These are the slides and the example code I used in my FFI lighting talk. Broadly the examples assume a POSIX operating system and the S.M.A.R.T. example assumes Linux but could be ported elsewhere easy enough. Be careful, the examples are arranged to fit on a projector screen more than correctness:)
== Examples
=== hello_world
Simple hello world example
=== hello
Example passing params to C function
=== inet_checksum
Example using pointers and semi-realistic computation
=== getpid
libc example that gets the current process id
=== S.M.A.R.T.
Native code returns pointers to structs containing hard drive diagnostic information (Linux specific)
== Presentation
showoff slides