AC_DEFINE_UNQUOTED(WINDOWS,1,[This is a Windows system])
AC_CHECK_HEADER(windows.h, , [AC_MSG_ERROR([** MinGW and no windows.h. I give up.])])
AC_CHECK_HEADER(winsock2.h, , [AC_MSG_ERROR([** MinGW and no winsock2.h. I give up.])])
AC_DEFINE_UNQUOTED(WINDOWS,1,[This is a Windows system])
AC_CHECK_HEADER(windows.h, , [AC_MSG_ERROR([** MinGW and no windows.h. I give up.])])
AC_CHECK_HEADER(winsock2.h, , [AC_MSG_ERROR([** MinGW and no winsock2.h. I give up.])])