[Dev-C++] Differences in compilers

[Danny A. <tam...@ms...>]

Hey guys this is probably a really stupid question but I got a problem I =
feel is totally compiler related.  I'm still using a book called "C++ PRO=
GRAMMING for the Absolute Beginner," and its compatible with a compiler c=
alled "CODE WARRIOR". I have typed out a very simple code for Windows 32 =
apps and I have an error "NULL not declared," and  below is the code.  I =
was just wondering what I might have to adjust or keep in mind when deali=
ng with different compilers because the author figures this will run no p=
roblem. =20

#include <windows.h>
//win32 entry-point routine
int WINAPI WinMain(HINSTANCE hInst,
                   HINSTANCE hPreInst, =20
                   LPSTR lpszCmdLine, =20
                   int nCmdShow)
{
    MessageBox(Null, "Windows Programming is Easy!!",
                     "My First Message Box",
                     MB_OKCANCEL | MB_ICONINFORMATION);
}