I have PHP script, which is requested by user. In this script I want to run C++ script(exe), but not wait until this script finishes(because this script does some post-process with data, which PHP doesn't care about). Is there anyway to do this on Apache?
You want the php exec function. Bear in mind the comment on the page about apache:
When calling exec() from within an apache php script, make sure to take care of stdout, stderr and stdin (as in the example below).