ATL / WTL / STL

// Mail Application.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#include "Mail Application.h"
#include <MAPI.h>

#ifdef _DEBUG
#define new DEBUG_NEW
#endif


// The one and only application object

CWinApp theApp;

using namespace std;

int _tmain(int argc, TCHAR* argv[], TCHAR* envp[])
{
	int nRetCode = 0;

	// initialize MFC and print and error on failure
	if (!AfxWinInit(::GetModuleHandle(NULL), NULL, ::GetCommandLine(), 0))
	{
		// TODO: change error code to suit your needs
		_tprintf(_T("Fatal Error: MFC initialization failed\n"));
		nRetCode = 1;
	}
	else
	{
		MapiRecipDesc sender;
		MapiRecipDesc recipient;
		MapiMessage note;
		HMODULE hinstMapi32Dll = NULL;

		if (hinstMapi32Dll == NULL)
			hinstMapi32Dll = ::LoadLibraryA("MAPI32.DLL");

		if (hinstMapi32Dll == NULL)
		{
			AfxMessageBox(AFX_IDP_FAILED_MAPI_LOAD);
			return -1;
		}
		ULONG (PASCAL *lpfnMAPISendMail)(ULONG, ULONG, MapiMessage*, FLAGS, ULONG);
		lpfnMAPISendMail = (LPMAPISENDMAIL)GetProcAddress( hinstMapi32Dll, "MAPISendMail");

		sender.ulReserved = 0;
		sender.ulRecipClass = MAPI_ORIG;
		sender.lpszName = "My Name";
		sender.lpszAddress = "me@myeamil.com";
		sender.ulEIDSize = 0;
		sender.lpEntryID = NULL;

		recipient.ulReserved = 0;
		recipient.ulRecipClass = MAPI_TO;
		recipient.lpszName = "Person Name";
		recipient.lpszAddress = "SMTP:towhomitmayconcern@email.com";
		recipient.ulEIDSize = 0;
		recipient.lpEntryID = NULL;

		note.ulReserved = 0;
		note.lpszSubject = "Subject goes here";
		note.lpszNoteText = "Message body goes here";
		note.lpszMessageType = NULL;
		note.lpszDateReceived = NULL;
		note.lpszConversationID = NULL;
		note.flFlags = 0L;
		note.lpOriginator = &sender;
		note.nRecipCount = 1;
		note.lpRecips = &recipient;
		note.nFileCount = 0;
		note.lpFiles = NULL;

		nRetCode = lpfnMAPISendMail( 0, 0L, &note, MAPI_DIALOG, 0L );

	}

	return nRetCode;
}

#include <stdio.h>

typedef void (*VoidFunctionPtr)(void);

void FunctionA()
{
	printf("You are in Function A.\n");
}

void FunctionB()
{
	printf("You are in Function B.\n");
}

int main(void)
{
	VoidFunctionPtr fp = FunctionA;
	fp();
}