Provides some of the missing POSIX file syscalls

src/trusted/desc/nacl_desc_semaphore.c

 /*
  * Copyright (c) 2012 The Native Client Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 /*
  * NaCl Service Runtime.  Semaphore Descriptor / Handle abstraction.
  */
 
@@ skipping 100 matching lines @@
   },
   NaClDescMapNotImplemented,
   NACL_DESC_UNMAP_NOT_IMPLEMENTED
   NaClDescReadNotImplemented,
   NaClDescWriteNotImplemented,
   NaClDescSeekNotImplemented,
   NaClDescPReadNotImplemented,
   NaClDescPWriteNotImplemented,
   NaClDescIoctlNotImplemented,
   NaClDescSemaphoreFstat,
+  NaClDescFchdirNotImplemented,
+  NaClDescFchmodNotImplemented,
+  NaClDescFsyncNotImplemented,
+  NaClDescFdatasyncNotImplemented,
+  NaClDescFtruncateNotImplemented,
   NaClDescGetdentsNotImplemented,
   NaClDescExternalizeSizeNotImplemented,
   NaClDescExternalizeNotImplemented,
   NaClDescLockNotImplemented,
   NaClDescTryLockNotImplemented,
   NaClDescUnlockNotImplemented,
   NaClDescWaitNotImplemented,
   NaClDescTimedWaitAbsNotImplemented,
   NaClDescSignalNotImplemented,
   NaClDescBroadcastNotImplemented,
   NaClDescSendMsgNotImplemented,
   NaClDescRecvMsgNotImplemented,
   NaClDescLowLevelSendMsgNotImplemented,
   NaClDescLowLevelRecvMsgNotImplemented,
   NaClDescConnectAddrNotImplemented,
   NaClDescAcceptConnNotImplemented,
   NaClDescSemaphorePost,
   NaClDescSemaphoreSemWait,
   NaClDescSemaphoreGetValue,
   NaClDescSetMetadata,
   NaClDescGetMetadata,
   NaClDescSetFlags,
   NaClDescGetFlags,
   NACL_DESC_SEMAPHORE,
 };