Ebixio

GEDCOM files sometimes have no indentation. That makes it difficult to read or edit them with a text editor. Using the following simple instructions, you can auto-indent the file so that it is more readable in the vim editor.

Compare the readability of the two formats

Save the next few lines into a file called gedcom_indent. Make the file executable and place it somewhere in your path.

#!/usr/bin/env python

from __future__ import print_function
import sys

for line in sys.stdin:
    line = line.lstrip()
    try:
        level = int(line.split(' ', 1)[0])
        print('\t' * level, end='')
    except:                                                                                                                                            
        pass
    print(line, end='', sep='')

Now add the following 2 lines to your ~/.vimrc file:

autocmd BufReadPost,FileReadPost *.ged %!gedcom_indent
autocmd FileType gedcom set foldmethod=indent nolist ts=4

This tells vim to filter any file with a “ged” extension through the small gedcom_indent filter (which will add leading tabs to the file). The second line tells it to make each TAB count for 4 spaces, and to fold based on indentation.

Git has a lot of commands. Well over 100 of them. Most of the times you only use a handful of them, but if you’re a power-user, every once in a while you’re looking for that elusive command that you remember reading about. This Git quick reference card sums them all up for you so you can look up the details using Git’s help system (git help <command>).

Git Quick Reference Card - Page 1

Git Quick Reference Card - Page 2

The reference card is available as a PDF so you can print it out. The PDF version is derived from the TeX file which is hosted at http://github.com/gburca/git-qrc so anyone can update it.

On a stock Ubuntu 11.04 distribution, wpa_cli can not talk to wpa_supplicant. Regardless of the options used, wpa_cli will always report:

Could not connect to wpa_supplicant - re-trying

That’s because wpa_cli expects to talk to wpa_supplicant over a control socket, but the default wpa_supplicant command line options don’t create a control socket (only the D-Bus interface is activated).

The fix is fairly easy. Modify the following file:

/usr/share/dbus-1/system-services/fi.epitest.hostap.WPASupplicant.service

and pass the -O option to wpa_supplicant by replacing the

Exec=/sbin/wpa_supplicant -u -s

line with

Exec=/sbin/wpa_supplicant -u -s -O /var/run/wpa_supplicant

Notice, that’s a capital-o, not a zero in the command line.

Restart the supplicant with: sudo killall wpa_supplicant and run ps auxww | grep wpa_supplicant to verify that the new options are being used.

If you notice that your changes are ignored, try making the same changes to:

/usr/share/dbus-1/system-services/fi.w1.wpa_supplicant1.service

You should now be able to run wpa_cli without any command line options (or with wpa_cli -p /var/run/wpa_supplicant) and talk to wpa_supplicant.

There are a number of solutions out there that allow you to back up your Google mail, but all of them have some significant shortcomings. That’s pretty surprising given the popularity of GMail. BaGoMa aims to address all (or most) of them.

1. BaGoMa is a command line application, so you can easily automate the backup. A GUI might be added in the future if there’s enough of a demand for it.
2. It runs on all major operating systems: Linux, Windows, Mac OS X, basically anything that Python runs on. For Windows users the zip file even contains a stand-alone executable that has the Python interpreter and libraries built-in, so you don’t need to install anything else.
3. It is open sourced, and contributions from the community are welcomed and encouraged. That also means you can read the source code  yourself to make sure your password and emails remain private.
4. It has no arbitrary limitations on the tag/label names you can use in Google. Some other solutions out there expect you to only use ASCII. That means non-English users are out of luck. It even auto-detects the main types of folders in use so that it can skip folders such as “Spam” and “Trash”.
5. Most importantly, it is tuned to work specifically with Google mail. There are a lot of generic applications that are able to backup an IMAP account. GMail however is not a true IMAP account. For example, if you apply 5 tags/labels to an email message, it shows up in 5 different IMAP folders. From the perspective of a regular IMAP application those look like 5 distinct messages, so they get backed up 5 times. It’s not clear what would happen when you attempt to restore your mail from such a backup. Will you end up with 5 identical copies of the message, each with a single tag/label, or will you end up with a single message that has 5 tags? BaGoMa does the right thing. In this case that means the message only gets downloaded (and backed up) once, and when restored all the original tags are applied to the same message.

The use of BaGoMa is extremely simple. To back up your account all you need is:

bagoma --email=your_user_id@gmail.com

It works seamlessly with Google Apps for Business, so if you’re hosting your business email with Google you can use your business email address instead of YourUserId@gmail.com to back up your business account. Please note that if you don’t specify a backup directory, BaGoMa will use a directory that matches your email address. Email addresses are case insensitive, but on operating systems with case-sensitive file systems you need to be consistent in how you write your email address, or specify the backup directory.

To restore your email you would run:

bagoma --email=your_user_id@gmail.com --action=restore

So what are you waiting for? Give it a try and stop worrying about forgetting your password and getting locked out of your account, or losing important emails if Google ever has an E-Mail outage.

BaGoMa homepage: http://sourceforge.net/p/bagoma/

BaGoMa downloads: http://sourceforge.net/projects/bagoma/files/

BaGoMa documentation: http://bagoma.sourceforge.net/

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 use 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.