[WIP] Yet another demo for BMM NaCl ppapi connection.

ipc/ipc_channel.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 IPC_IPC_CHANNEL_H_
 #define IPC_IPC_CHANNEL_H_
 
 #include <string>
 
 #if defined(OS_POSIX)
@@ skipping 184 matching lines @@
   // require additional this is simply calls GenerateUniqueRandomChannelID().
   // For portability the prefix should not include the \ character.
   static std::string GenerateVerifiedChannelID(const std::string& prefix);
 #endif
 
 #if defined(OS_LINUX)
   // Sandboxed processes live in a PID namespace, so when sending the IPC hello
   // message from client to server we need to send the PID from the global
   // PID namespace.
   static void SetGlobalPid(int pid);
+
+  // On POSIX an IPC::Channel wraps a socketpair() with set some attributes

[Mark Seaborn, 2014/02/07 22:53:43]

"with some attributes set"

However, since this is documenting the interface it probably shouldn't specify
implementation details.  So I'd just say "SocketPair() returns a pair of socket
FDs suitable for using with IPC::Channel".

+  // (such as non-blocking mode). This returns raw FD #s for the pair, which
+  // allows us to pass file descriptors between processes (such as between
+  // a plugin process and the browser process) before actual initialization
+  // of IPC server Channel instance.
+  static bool SocketPair(int* fd1, int* fd2);
 #endif
 
  protected:
   // Used in Chrome by the TestSink to provide a dummy channel implementation
   // for testing. TestSink overrides the "interesting" functions in Channel so
   // no actual implementation is needed. This will cause un-overridden calls to
   // segfault. Do not use outside of test code!
   Channel() : channel_impl_(0) { }
 
  private:
   // PIMPL to which all channel calls are delegated.
   class ChannelImpl;
   ChannelImpl *channel_impl_;
 };
 
 }  // namespace IPC
 
 #endif  // IPC_IPC_CHANNEL_H_