Can 32 bit and 64 bit work together?

Question

Can 64 bit library work in a 32 bit application? For example, my application GUI uses 32 bit Qt. And my business core is a 64 bit library. The OS is 64 bit. Can they work to

Answer 1

I'm working on an application that does exactly this. The application core is x64 (and uses Qt), but it has to communicate with some equipment, for which I only have 32bit library from manufacturer. The way I implemented it is having two applications 64bits for core and GUI, and 32bits that controls the equipment and communicates with the main applications using QSharedMemory. Both apps are based on Qt (64 and 32bits correspondingly).