Well, I'm finally back from my conference run. Despite some shortcomings with hotel 'net connections, nothing went badly.
One thing I'm particularly pleased with is that I got to write some code (feels like a long time since I had the luxury to write pleasure code). I'm about 50% of the way through a libffi extension for PHP 5 (the ffi page is out of date, but still relevant).
FFI is an acronym for Foreign Function Interface and it provides a portable way to make calls from PHP into C code (and vice versa) at run-time, without having to write glue specifically for the function being called at compile-time.
PHP already has a w32api interface (unmaintained and broken) that does the same thing but for windows; my ffi extension replaces it and will also work on other platforms (Linux, Darwin, SunOS, Irix, Alpha, m68k, PowerPC and Arm).
Not only can you map functions from shared libraries (and DLLs), but you can also define structured types and access them using a natural syntax (taking advantage of the new OO internals in ZE2).
Even better is that you will also be able to pass PHP functions directly to mapped C functions that take callbacks as parameters (like the C library function qsort).
This all sounds really cool, but there is a price - allowing a PHP script to do this stuff is extremely dangerous (hence the title of this entry), so you won't find it on shared hosters.