Plumbing though mode parameter to open, since fusefs can make use of it.

native_client_sdk/src/libraries/nacl_io/kernel_proxy.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef LIBRARIES_NACL_IO_KERNEL_PROXY_H_
 #define LIBRARIES_NACL_IO_KERNEL_PROXY_H_
 
 #include <map>
 #include <string>
 
@@ skipping 49 matching lines @@
 
   void SetMountCallback(nacl_io_mount_callback_t mount_callback,
                         void* user_data);
 
   virtual int pipe(int pipefds[2]);
 
   // NaCl-only function to read resources specified in the NMF file.
   virtual int open_resource(const char* file);
 
   // KernelHandle and FD allocation and manipulation functions.
-  virtual int open(const char* path, int open_flags);
+  virtual int open(const char* path, int open_flags, mode_t mode_flags);
   virtual int close(int fd);
   virtual int dup(int fd);
   virtual int dup2(int fd, int newfd);
 
   virtual void exit(int status);
 
   // Path related System calls handled by KernelProxy (not filesystem-specific)
   virtual int chdir(const char* path);
   virtual char* getcwd(char* buf, size_t size);
   virtual char* getwd(char* buf);
@@ skipping 168 matching lines @@
   virtual int AcquireSocketHandle(int fd, ScopedKernelHandle* handle);
 #endif
 
   ScopedEventEmitter signal_emitter_;
   DISALLOW_COPY_AND_ASSIGN(KernelProxy);
 };
 
 }  // namespace nacl_io
 
 #endif  // LIBRARIES_NACL_IO_KERNEL_PROXY_H_