Call a function before main [duplicate]

Question

Possible Duplicate:
Is main() really start of a C++ program?

Is possible to call my function before program's startup? How can i do this work in C++ or C?

Answer 1

You can have a global variable or a static class member.

1) static class member

//BeforeMain.h class BeforeMain {     static bool foo; };  //BeforeMain.cpp #include "BeforeMain.h" bool BeforeMain::foo = foo(); 

2) global variable

bool b = foo(); int main() { } 

Note this link - Mirror of http://www.parashift.com/c++-faq-lite/ctors.html#faq-10.14 / proposed alternative - posted by Lundin.

Answer 2

In C++ there is a simple method: use the constructor of a global object.

class StartUp { public:    StartUp()    { foo(); } };  StartUp startup; // A global instance  int main() {     ... } 

This because the global object is constructed before main() starts. As Lundin pointed out, pay attention to the static initialization order fiasco.