Provide IRT process interface

src/untrusted/nacl/pipe.c

 /*
  * Copyright (c) 2013 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.
  */
 
 #include <errno.h>
 #include <unistd.h>
 
-#include "native_client/src/untrusted/nacl/nacl_irt.h"
-
-int fsync(int fd) {
-  if (!__libnacl_irt_init_fn(&__libnacl_irt_dev_fdio.fsync,
+int pipe(int fd[2]) {
+  if (!__libnacl_irt_init_fn(&__libnacl_irt_dev_fdio.pipe,
                              __libnacl_irt_dev_fdio_init)) {
     return -1;
   }
 
-  int error = __libnacl_irt_dev_fdio.fsync(fd);
+  int error = __libnacl_irt_dev_fdio.pipe(fd);
   if (error) {
     errno = error;
     return -1;
   }
 
   return 0;
 }