how to define a custom entry point

hello all,
I am just wondering if anyone could please tell me how/where I can define a custom entry point in Visual C++ 6.0?

I created my project/workspace as "A Win32 Application" with an empty workspace. but I will not be using the traditional Windows application entry point:

Code:

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int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow)

---

I will be using:

Code:

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int Entry(void)

---

I don't need all the parameters/local variables that WinMain supplies.

can anyone tell me how to do this? I think its possible in Project -> Settings but can't find where, and I also think its possible by a #pragma comment.


thanks! :)

You could always do something like this (leaving out the parameter names if you're using C++ to avoid warnings):

Code:

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int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow) {
    Entry();
    return 0;
}

---

But I'm sure you've thought of that. :)

Why do you want to change the entry point? If you simply don't need the parameters and are using C++, try this:

Code:

---

int WINAPI WinMain(HINSTANCE, HINSTANCE, LPSTR, int) {
    // code
}

---

It's easy in assembly, but I'm afraid it's not possible in C++...

Sure it is. It's just pretty silly.

Code:

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$ cat entrypoint.c
#include <windows.h>

#ifndef ENTRYPOINT
    #error You must define ENTRYPOINT
#endif

void ENTRYPOINT(void);

int WINAPI WinMain(HINSTANCE, HINSTANCE, LPSTR, int) {
    ENTRYPOINT();
    return 0;
}
$ cat customentry.c
#include <iostream>

void ENTRYPOINT(void) {
    std::cout << "Hello, World!\n";
}
$ gcc entrypoint.c customentry.c -o customentry -DENTRYPOINT=Entry
$ ./customentry
Hello, World!
$

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The entry point is still WinMain...

Yes but you can pretend it's ENTRYPOINT because as far as customentry.c is concerned it is.

LOL that is stupid...

found out how from some open source yesterday:

Code:

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#pragma comment(linker, "/ENTRY:Entry")

---

:)

Now that's the real deal :D

Quote:

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Originally Posted by maxorator

It's easy in assembly, but I'm afraid it's not possible in C++...

---

It's not language specific. Defining custom entry points is a feature of your linker. Hence, your ability to do this depends on your linker in question. The previous code will work in Microsoft compilers. GCC & Co. is a different story.

It should be noted that the actual default entry function for MSVC is not WinMain but WinMainCRTStartup (or similar variant). This function initialises the C run-time, calls C++ constructors for global variables and then calls WinMain. Once WinMain returns, it does run-time cleanup, calls global destructors, and finally calls ExitProcess. Therefore, if you define your own entry function, you can not use the C or C++ run-time libraries or C++ global variables. You must also call ExitProcess at the end of your entry function as there is nothing to return to. There is some more information on this topic in the LIBCTINY article.