Function prototype in seperate file , 3 file help c++?

Hey


I've got a c++ query. Ive got currently 2 files. One is the main , whilst the other file is a seperate bool function, which is used by the main file when running the program.


I want to create another file (ie : fun.h) which stores the prototype of the bool function.


What do i have to write in each file, so all 3 files connect to each other, and so that when all 3 files compiled together, no syntax errors occur.





thankyou :-)