+#if wxUSE_GUI && defined(__WXMSW__)
+
+#if wxUSE_UNICODE && !defined(__WXWINCE__)
+ #define NEED_UNICODE_CHECK
+#endif
+
+#ifdef NEED_UNICODE_CHECK
+
+// check whether Unicode is available
+static bool wxIsUnicodeAvailable()
+{
+ static const wchar_t *ERROR_STRING = L"wxWidgets Fatal Error";
+
+ if ( wxGetOsVersion() != wxOS_WINDOWS_NT )
+ {
+ // we need to be built with MSLU support
+#if !wxUSE_UNICODE_MSLU
+ // note that we can use MessageBoxW() as it's implemented even under
+ // Win9x - OTOH, we can't use wxGetTranslation() because the file APIs
+ // used by wxLocale are not
+ ::MessageBox
+ (
+ NULL,
+ L"This program uses Unicode and requires Windows NT/2000/XP.\n"
+ L"\n"
+ L"Program aborted.",
+ ERROR_STRING,
+ MB_ICONERROR | MB_OK
+ );
+
+ return false;
+#else // wxUSE_UNICODE_MSLU
+ // and the MSLU DLL must also be available
+ HMODULE hmod = ::LoadLibraryA("unicows.dll");
+ if ( !hmod )
+ {
+ ::MessageBox
+ (
+ NULL,
+ L"This program uses Unicode and requires unicows.dll to work "
+ L"under current operating system.\n"
+ L"\n"
+ L"Please install unicows.dll and relaunch the program.",
+ ERROR_STRING,
+ MB_ICONERROR | MB_OK
+ );
+ return false;
+ }
+
+ // this is not really necessary but be tidy
+ ::FreeLibrary(hmod);
+
+ // finally do the last check: has unicows.lib initialized correctly?
+ hmod = ::LoadLibraryW(L"unicows.dll");
+ if ( !hmod )
+ {
+ ::MessageBox
+ (
+ NULL,
+ L"This program uses Unicode but is not using unicows.dll\n"
+ L"correctly and so cannot work under current operating system.\n"
+ L"Please contact the program author for an updated version.\n"
+ L"\n"
+ L"Program aborted.",
+ ERROR_STRING,
+ MB_ICONERROR | MB_OK
+ );
+
+ return false;
+ }
+
+ ::FreeLibrary(hmod);
+#endif // !wxUSE_UNICODE_MSLU
+ }
+
+ return true;
+}
+
+#endif // NEED_UNICODE_CHECK