diff --git a/winsup/cygwin/ntdll.h b/winsup/cygwin/ntdll.h
index 64babefc3..d64de1b9a 100644
--- a/winsup/cygwin/ntdll.h
+++ b/winsup/cygwin/ntdll.h
@@ -161,7 +161,9 @@ extern GUID __cygwin_socket_guid;
 #define FSCTL_PIPE_DISCONNECT	CTL_CODE(FILE_DEVICE_NAMED_PIPE, 1, \
 					 METHOD_BUFFERED, FILE_ANY_ACCESS)
 #define FSCTL_PIPE_LISTEN	CTL_CODE(FILE_DEVICE_NAMED_PIPE, 2, \
-					 METHOD_BUFFERED, FILE_ANY_ACCESS)
+					METHOD_BUFFERED, FILE_ANY_ACCESS)
+#define FSCTL_PIPE_PEEK		CTL_CODE(FILE_DEVICE_NAMED_PIPE, 3, \
+					 METHOD_BUFFERED, FILE_READ_DATA)
 #define FSCTL_PIPE_WAIT		CTL_CODE(FILE_DEVICE_NAMED_PIPE, 6, \
 					 METHOD_BUFFERED, FILE_ANY_ACCESS)
 #define FSCTL_PIPE_IMPERSONATE	CTL_CODE(FILE_DEVICE_NAMED_PIPE, 7, \
@@ -1466,6 +1468,7 @@ extern "C"
 			       PLARGE_INTEGER, ULONG);
   NTSTATUS NTAPI NtUnlockVirtualMemory (HANDLE, PVOID *, PSIZE_T, ULONG);
   NTSTATUS NTAPI NtUnmapViewOfSection (HANDLE, PVOID);
+  NTSTATUS NTAPI NtWaitForSingleObject (HANDLE, BOOLEAN, PLARGE_INTEGER);
   NTSTATUS NTAPI NtWriteFile (HANDLE, HANDLE, PIO_APC_ROUTINE, PVOID,
 			      PIO_STATUS_BLOCK, PVOID, ULONG, PLARGE_INTEGER,
 			      PULONG);