Something

#include <windows.h>
#pragma comment(linker, "/align:0x8000")
#pragma comment(lib, "user32.lib")
#define LogFile "c:\\LOG.txt"
#define Append(text, h) AppendLog(text, strlen(text), h)

HANDLE hLogFile;
HANDLE OpenLog(char* Filename);
BOOL CloseLog(HANDLE h);
DWORD AppendLog(char *str, DWORD uSize, HANDLE h);

BOOL WINAPI DllMain(IN HINSTANCE hinstDll, IN DWORD dwReason,LPVOID lpvReserved)
{
    switch (dwReason)
    {
        case DLL_PROCESS_ATTACH:
			MessageBox(NULL, "Hello from the Process!", "DLL Injection Test" ,MB_OK|MB_ICONINFORMATION|MB_SYSTEMMODAL);
			hLogFile = OpenLog(LogFile);
			Append("\r\n************************\r\nDLL_PROCESS_ATTACH\r\n",hLogFile);
			CloseLog(LogFile);
			break;
    }
    return TRUE;
}


HANDLE OpenLog(char *Filename)
{
	HANDLE hLogFile;

	hLogFile = CreateFile( Filename, GENERIC_WRITE, FILE_SHARE_READ, 0, OPEN_ALWAYS,0,0);
	
	return hLogFile;
}

BOOL CloseLog(HANDLE h)
{
	return CloseHandle(h);
}

//returns written bytes
DWORD AppendLog(char *str, DWORD uSize, HANDLE h)
{
	DWORD written;

	SetFilePointer( h, 0, 0, FILE_END );
	WriteFile(h, str, uSize, &written, 0);

	return written;
}