You can't really directly export a function from an exe to another process, I guess it would help to understand what it is you're trying to achieve
If you've got some really cool code you want to re-use somewhere else, pull that code into a DLL and use it from both exes
If you want some form of inter-process communication, you have a number of options, including
1. COM/RPC - but this is a sledgehammer to crack a nut
2. Mailslots/Pipes/Sockets - if you just need to move data between
3. MemoryMapped files - if you want to share memory
take a look at
http://msdn.microsoft.com/en-us/library/aa365574(VS.85).aspx[
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