error LNK2005: _main already defined

Source:  http://social.msdn.microsoft.com/Forums/en-US/vclanguage/thread/cf3b6326-6e58-4b85-afb1-2694a1450128/

I recently installed VC++ 2005 EXP edition.

1) I created a project name Radius and created two new items hello.cpp and area.cpp.

2) area.cpp is the first item and hello.cpp is the second one.

3) When I build the project Radius, I got the error

LNK2005: _main already defined in area.obj

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This error is because of multiple definitions of main. You must have defined main in area.cpp as well as in hello.cpp. In C/C++ programs, you can write only one main per application.

Remove one definition of main and it should work fine.

Cheers

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I think what you are trying to do is....

---

1.) File: hello.cpp

#include <IOSTREAM>
#include <RADIUS.H>

int main(int argc, char *argv[])
{
      float area = get_area(5);
      printf("Area of circle with radius %d = %f\n", 5, area);
}

2.) File: radius.h

float get_area(float radius);
float get_circumference(float radius);

3.) File: radius.cpp

#include <RADIUS.H>

float get_area(float radius)
{
     return (3.14159 * radius * radius);
}

float get_circumference(float radius)
{
     return (3.14159 * (radius * 2));
}