Fuchsia: Partial implementation of dart:io sockets

runtime/bin/fdutils.h

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef RUNTIME_BIN_FDUTILS_H_
 #define RUNTIME_BIN_FDUTILS_H_
 
 #include "bin/builtin.h"
 #include "platform/globals.h"
 
@@ skipping 21 matching lines @@
   // which case it returns -1 and errno is still valid. The file
   // descriptor must be in blocking mode.
   static ssize_t ReadFromBlocking(int fd, void* buffer, size_t count);
 
   // Writes the requested number of bytes to a file descriptor. This
   // function will only return on short writes if an error occours in
   // which case it returns -1 and errno is still valid. The file
   // descriptor must be in blocking mode.
   static ssize_t WriteToBlocking(int fd, const void* buffer, size_t count);
 
+  // Closes fd without modifying errno.
+  static void SaveErrorAndClose(intptr_t fd);
+
  private:
   DISALLOW_ALLOCATION();
   DISALLOW_IMPLICIT_CONSTRUCTORS(FDUtils);
 };
 
 }  // namespace bin
 }  // namespace dart
 
 #endif  // RUNTIME_BIN_FDUTILS_H_