LINK : fatal error LNK1561: entry point must be defined ERROR IN VC++

Question

I installed MS VS VC++ for the first time in order to start programming OpenGL with GLFW library. I follower instructions on how to install it over at http://shawndeprey.blogspot.com/2012/02/setting-up-glfw-in-visual-studio-2010.html Then I wrote this simple program, just to test it, which did work on Eclipse:

#include <stdlib.h> #include <GL/glfw.h>  using namespace std;  int main() {     int running = GL_TRUE;     if (!glfwInit()) {         exit(EXIT_FAILURE);     }      if (!glfwOpenWindow(300, 300, 0, 0, 0, 0, 0, 0, GLFW_WINDOW)) {         glfwTerminate();         exit(EXIT_FAILURE);     }      while (running) {         // glClear( GL_COLOR_BUFFER_BIT );         glfwSwapBuffers();         running = !glfwGetKey(GLFW_KEY_ESC) && glfwGetWindowParam(GLFW_OPENED);     }      glfwTerminate();     exit(EXIT_SUCCESS);     return 0; } 

But then I got this awful error:

------ Build started: Project: first1, Configuration: Debug Win32 ------    LINK : fatal error LNK1561: entry point must be defined ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ========== 

I know, I've looked around on the internet and the only solution I found was "It requires main() function in order to work". I obviously have it, right there, but it still throws me the same fatal error :(

Would be great to get response on how to fix it. There might me a flaw in the installation process or something.

Answer 1

Is this a console program project or a Windows project? I'm asking because for a Win32 and similar project, the entry point is WinMain().

1. Right-click the Project (not the Solution) on the left side.
2. Then click Properties -> Configuration Properties -> Linker -> System

If it says Subsystem Windows your entry point should be WinMain(), i.e.

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPWSTR lpCmdLine, int nShowCmd) {    your code here ... } 

Besides, speaking of the comments. This is a compile (or more precisely a Link) error, not a run-time error. When you start to debug, the compiler needs to make a complete program (not just to compile your module) and that is when the error occurs.

It does not even get to the point being loaded and run.