C++ integration with PHP

Does anyone know how to integrate C++ and PHP if there are some data changes between PHP program and C++ program? What I can think about is: in PHP, put the data in a file, and use "system" call to activate the c++ program. After that, let the c++ program to read the data file, and output the result into another file, and let the PHP to read the result file. But there is one question: will php wait until C++ program finish if I use "system" function from PHP? Is there any better way to do the integration? Thanks, G.Z.