diff --git a/include/winbase.h b/include/winbase.h
index 4c1d86e12db..9d59e4d3af1 100644
--- a/include/winbase.h
+++ b/include/winbase.h
@@ -2113,6 +2113,7 @@ WINBASEAPI BOOL        WINAPI GetNamedPipeHandleStateA(HANDLE,LPDWORD,LPDWORD,LP
 WINBASEAPI BOOL        WINAPI GetNamedPipeHandleStateW(HANDLE,LPDWORD,LPDWORD,LPDWORD,LPDWORD,LPWSTR,DWORD);
 #define                       GetNamedPipeHandleState WINELIB_NAME_AW(GetNamedPipeHandleState)
 WINBASEAPI BOOL        WINAPI GetNamedPipeInfo(HANDLE,LPDWORD,LPDWORD,LPDWORD,LPDWORD);
+WINBASEAPI BOOL        WINAPI GetNamedPipeClientProcessId(HANDLE,PULONG);
 WINBASEAPI VOID        WINAPI GetNativeSystemInfo(LPSYSTEM_INFO);
 WINBASEAPI BOOL        WINAPI GetNumaProcessorNode(UCHAR,PUCHAR);
 WINADVAPI  BOOL        WINAPI GetNumberOfEventLogRecords(HANDLE,PDWORD);