sfc_os: Add a prototype for SfcIsKeyProtected().
diff --git a/include/sfc.h b/include/sfc.h
index 7a76928..949e6b3 100644
--- a/include/sfc.h
+++ b/include/sfc.h
@@ -36,6 +36,7 @@
 
 BOOL WINAPI SfcGetNextProtectedFile(HANDLE, PPROTECTED_FILE_DATA);
 BOOL WINAPI SfcIsFileProtected(HANDLE, LPCWSTR);
+BOOL WINAPI SfcIsKeyProtected(HKEY, LPCWSTR, REGSAM);
 BOOL WINAPI SfpVerifyFile(LPCSTR, LPSTR, DWORD);
 
 #ifdef __cplusplus