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The information below comes from a number of sources, including my own experiments with the Android IPC and some disparate internet sources.

The overall architecture of the Android IPC system is shown in the diagram below. It consists of four major blocks; one in kernel space, and the other three in user space. The dashed lines represent the logical RPC calls. The solid lines represent the actual data flow.

• BinderDriver: This is the core of IPC system. It passes data between a ServiceProvider(s) and a ServiceUser(s). This kernel component is provided by Android.
• ServiceProvider: Provides some kind of service. It parses the received RPC data from the BinderDriver and does the real work. Application developers will either make use of existing service providers (such as the Camera or AudioFlinger), or in some cases will write their own.
• ServiceManager: This is a special singleton ServiceProvider that provides service manager services for other service providers. This component is provided by Android.
• ServiceUser: This is the client. It remote calls the ServiceProvider by generating an RPC and sending it to the BinderDriver. Application developers typically write their own ServiceUser as part of their application.

Here is a typical flow of events for a fictitious MultServiceProvider (a service provider that multiplies two numbers for a client) and a MultServiceUser client which doesn’t know how to do multiplication (maybe because the numbers are quaternions) and needs to use the MultServiceProvider:

1. ServiceManager runs first (at power-up) and registers a special node (node O) with the BinderDriver.
2. The MultServiceProvider gets an IServiceManager proxy object for the special node O by calling the global defaultServiceManager() function.
3. The MultServiceProvider then calls defaultServiceManager()->addService("Multiplier", new MultServiceProvider()) to add itself as a service provider and then waits in an infinite loop for someone to request its services. The addService RPC call is routed to the ServiceManager through the BinderDriver.
4. The BinderDriver notices that the RPC is for the ServiceManager to add a new service, so besides routing the RPC to the ServiceManager it generates another node (let’s call it node M), for the new MultServiceProvider.
5. The ServiceManager reads the data from the BinderDriver and processes the IServiceManager::addService RPC call.
6. The MultServiceUser client process gets an IServiceManager proxy object for the special node O (again by using defaultServiceManager()).
7. The client does an IServiceManager::getService("Multiplier") RPC call to get the MultServiceProvider. This call is routed to the ServiceManager through the BinderDriver.
8. The ServiceManager reads the RPC data from the BinderDriver, processes the IServiceManager::getService request and returns back the node representing the MultServiceProvider.
9. MultServiceUser calls MultServiceProvider::multiply(a, b). This call is routed to  the MultServiceProvider by the BinderDriver.
10. The MultServiceProvider handles the MultServiceProvider::multiply RPC call and sends the product of the 2 numbers in a reply to the BinderDriver.
11. The BinderDriver routes the reply back to the client.
12. The client reads the data from the BinderDriver which contains the result of “a * b”.

In a future post I hope to discuss the whole architecture in more detail, with concrete code examples for how to use IBinder, IInterface, BBinder, BpInterface, BnInterface, etc… to create a ServiceProvider and a ServiceUser all in native C++ code on Android.

Here’s a simple script that lets you toggle on or off your internet proxy in Windows. Save it to a file called Proxy.vbs on your desktop and double-click the file to execute the script.film Despicable Me 3

As shown below, the script will not change the proxy server address, but will simply turn it ON or OFF. If you want to also modify the proxy server and exception list every time you turn it on, update lines 37 and 38, and uncomment lines 40-41.Watch Full Movie Online Streaming Online and Download

Parts of this script come from a comment someone posted on a web site, but I no longer have the link to provide proper attribution.

Const HKCU=&H80000001 'HKEY_CURRENT_USER
Const HKLM=&H80000002 'HKEY_LOCAL_MACHINE

Const REG_SZ		= 1
Const REG_EXPAND_SZ	= 2
Const REG_BINARY	= 3
Const REG_DWORD		= 4
Const REG_MULTI_SZ	= 7
Const HKCU_IE_PROXY	= "Software\Microsoft\Windows\CurrentVersion\Internet Settings"

Set oReg=GetObject("winmgmts:!root/default:StdRegProv")

Main

Sub Main()
	buttons = vbQuestion + vbYesNoCancel + vbDefaultButton1

	If GetValue(HKCU,HKCU_IE_PROXY,"ProxyEnable",REG_DWORD) = 1 AND _
	Len(GetValue(HKCU,HKCU_IE_PROXY,"ProxyServer",REG_SZ)) > 0 Then
		' If Proxy is set then default to turning it off
		buttons = buttons + vbDefaultButton2
	End If

	choice = MsgBox("Enable the internet proxy?", buttons, "Proxy setting")
	If choice = vbYes Then
		SetProxy True
	ElseIf choice = vbNo Then
		SetProxy False
	End If
End Sub

Sub SetProxy(enabled)
	If enabled = False Then
		CreateValue HKCU,HKCU_IE_PROXY,"ProxyEnable",0,REG_DWORD
		MsgBox "Proxy Disabled", vbInformation, "Proxy OFF"
	Else
		strProxyServer = "MyProxySvr:80"
		strProxyOveride = "*.domain.com;*.domain2.com;*domain3.com"
	
		'CreateValue HKCU,HKCU_IE_PROXY,"ProxyServer",strProxyServer,REG_SZ
		'CreateValue HKCU,HKCU_IE_PROXY,"ProxyOverride",strProxyOveride,REG_SZ
		CreateValue HKCU,HKCU_IE_PROXY,"ProxyEnable",1,REG_DWORD
		MsgBox "Proxy Enabled and set to:" & vbcrlf & "(" & strProxyServer & ")", vbInformation, "Proxy ON"
	End If
End Sub

Function CreateValue(Key,SubKey,ValueName,Value,KeyType)
	Select Case KeyType
	Case REG_SZ
		CreateValue = oReg.SetStringValue(Key,SubKey,ValueName,Value)
	Case REG_EXPAND_SZ
		CreateValue = oReg.SetExpandedStringValue(Key,SubKey,ValueName,Value)
	Case REG_BINARY
		CreateValue = oReg.SetBinaryValue(Key,SubKey,ValueName,Value)
	Case REG_DWORD
		CreateValue = oReg.SetDWORDValue(Key,SubKey,ValueName,Value)
	Case REG_MULTI_SZ
		CreateValue = oReg.SetMultiStringValue(Key,SubKey,ValueName,Value)
	End Select
End Function

Function DeleteValue(Key, SubKey, ValueName)
	DeleteValue = oReg.DeleteValue(Key,SubKey,ValueName)
End Function

Function GetValue(Key, SubKey, ValueName, KeyType)
	Dim Ret

	Select Case KeyType
	Case REG_SZ
		oReg.GetStringValue Key, SubKey, ValueName, Value
		Ret = Value
	Case REG_EXPAND_SZ
		oReg.GetExpandedStringValue Key, SubKey, ValueName, Value
		Ret = Value
	Case REG_BINARY
		oReg.GetBinaryValue Key, SubKey, ValueName, Value
		Ret = Value
	Case REG_DWORD
		oReg.GetDWORDValue Key, SubKey, ValueName, Value
		Ret = Value
	Case REG_MULTI_SZ
		oReg.GetMultiStringValue Key, SubKey, ValueName, Value
		Ret = Value
	End Select

	GetValue = Ret
End Function

Many of the default ANSI colors used by the CygWin terminal are almost unreadable. For example, the blue that is used for directories in a file listing is pretty dark and hard to read on a black background. This limits the color palette that can be used in things such as the PS1 shell prompt. Try the following script (colortable16.sh) to see what your colors currently look like.

The colors can be changed by clicking on the system menu in the upper-left corner and selecting “Properties”. I decided to use the same colors as the Gnome terminal.

This is how the colors are defined in CygWin by default:

This is how they should be changed so that they’re more usable:

There’s no shortage of tutorials on how to use X11’s remote display facilities. On modern, properly configured systems, all you need to do is to use the -X or -Y option to ssh, and the magic is all taken care of by ssh and xauth. Unfortunately, sometimes servers are mis-configured and this simple solution doesn’t work.

On one server I was trying to use, sshd was compiled with a hard-coded path for xauth that was incorrect. This is easy to see when adding the “-v” switch to ssh. Look for:

debug1: Requesting X11 forwarding with authentication spoofing.
debug1: Remote: No xauth program; cannot forward with spoofing.

With no admin rights on the server, the normal work-around is to use the XAuthLocation option on the client side, either in the ~/.ssh/config file, or on the command line: ssh -o XAuthLocation=/proper/path. Some versions of sshd (including the one I was using) ignore this option.

Since I was working in a fairly secure environment, I decided to skip ssh/xauth part, and just set the DISPLAY environment variable on the server to “DISPLAY=my.client.ip:0.0”. That’s all nice and dandy, but my Ubuntu client was using Unix domain sockets instead of TCP for X11 so there was no way to connect to it remotely. First I tried modifying /etc/X11/xinit/xserverrc on the client to remove the “-nolisten tcp” option. That didn’t seem to do the trick (there was nobody listening on port 6000 after I restarted X). It turns out gdm has a different configuration file that also needs to be modified. I then changed /etc/gdm/gdm.schemas to:

     <schema>
       <key>security/DisallowTCP</key>
       <signature>b</signature>
      <default>false</default>
     </schema>

After X was restarted, I had X11 listening on port 6000. All that was left to do was to allow the server to connect (xhost +server.name.com) and everything was working like a charm.

Before you open up X11 to remote TCP connections as shown above, make sure you read up on it and understand the security implications.

In Ubuntu 10.04, MediaTomb is compiled without JavaScript (libjs) support, so if you try to use JavaScript for your layout you will be presented in the log files with:

ERROR: MediaTomb was compiled without js support, however you specified “js” to be used for the virtual-layout.

To remedy the situation, the first thing you need to do is to install libjs (SpiderMonkey).

Next you need to download the MediaTomb source (line 2 below) and all its development dependencies (line 1) so that it can be rebuilt with the newly installed libjs (change to root first, or prefix the lines below with “sudo”).

apt-get build-dep mediatomb
apt-get source mediatomb
vim mediatomb-0.12.0~svn2018/debian/rules

In the debian/rules file, search for MEDIATOMB_CONFIG_OPTIONS and change –disable-libjs to –enable-libjs. You should also update the changelog file (in the same debian directory) and perhaps the mediatomb_0.12.0~svn2018-6ubuntu2.dsc file to change the version. When done with the edits, run dpkg-buildpackage -rfakeroot -us -uc from the same directory you executed “apt-get” in.

If all goes well, you should see 3 new deb files in your current directory. Install them all (dpkg -i mediatomb*.deb) and start enjoying your JavaScript enabled MediaTomb.

To revert back to the original: apt-get install --reinstall mediatomb