Two 'main' functions in C/C++

Question

Can I write a program in C or in C++ with two main functions?

Answer 1

You can write it, and it'll compile, but it won't link (unless your linker is non-comformant)

Answer 2

Not in C, C++

but now C#.net introduce trick you can use 2 mains in one application. i implemented in my application too. I have scenario and requirement and implemented it successfully.

reference and proof is here https://www.youtube.com/watch?v=KJcBj3hLIpM

Answer 3

If one is static and resides in a different source file I don't see any problem.

Answer 4

In some very special architecture, you can. This is the case of the Cell Processor where you have a main program for the main processor (64-bit PowerPC Processors Element called PPE) and one or many main program for the 8 different co-processor (32-bit Synergistic Processing Element called SPE).

Answer 5

Yes , Multiple main() are allowed but not in global namespace.

"Every C++ program must have exactly one global function named main()" - Bjarne stroustrup.

Eg 1 :

namespace foo
{
  int main() //Main 1 
  {
    return 1;
  }
}

int main() // Main 2   
{

}

// Main 1 : namespace is foo

// Main 2 : namespace is global

// Allowed : Yes , its allowed as both the main() are present in different namespaces.

Eg 2 :

int main() //Main 1 
{
    return 1;
}

void main() // Main 2   
{

}

// Main 1 : namespace is global

// Main 2 : namespace is global

// Allowed : No , as multiple main() in global namespace . Compile-time error is thrown : redefinition of main() .. 

Answer 6

No,The main() is the entry point to your program,since u can't have two entry points you cant have two main().