Windows Portable Executable (PE) File Format

Great articles by Matt Pietrek that discuss the PE format in-depth:

• http://msdn2.microsoft.com/en-us/magazine/cc301805.aspx
  
• http://msdn2.microsoft.com/en-us/magazine/ms809762.aspx
  

Bash 'for' loop examples

I can never remember the syntax for bash for loops:

#!/bin/bash
for i in $( ls ); do
    echo item: $i
done

#!/bin/bash
for i in `seq 1 10`; do
        echo $i
done

#!/bin/bash
for ((i=100;i<=115;i+=1)); do
        echo $i
        sleep 1
        echo $i > /dev/ttyS1
done 

PenguinTV broken on Gutsy

I have been using PenguinTV to download the radio shows I subscribe to. The interface is OK, except:

• The multiple download feature is broken. You can't select muliple files and get it to download. Sucky!
  
• It is totally broken on Ubuntu Gutsy (segfaults). The workaround is:
  

  
  export LD_LIBRARY_PATH=/usr/lib/firefox
  export MOZILLA_FIVE_HOME=/usr/lib/firefox
  PenguinTV
  

  
  

HOWTO write a firefox plugin

I'm in the process of writing my first firefox plugin and have recorded my experiences here. The HOWTOs and links I used were:

• http://www.rietta.com/firefox/Tutorial/overview.html
  
• Chrome spec
  
• I found this hilarious:

  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"

  
  
• Good links from this blog
  
• HOWTO set up a development environment
  
• How to debug extensions, and some essential development extensions
  
• XUL Tutorials
  
• More XUL Tutorials
  
• Adding XUL elements (e.g. menus) dynamically
  
• XUL Reference
  
• Working with the tabbed browser
  
• Storing session information per tab
  
• Firefox extension preferences
  
• XMLHttpRequest
  
• Parsing XML
  
• Publishing the extension on addons.mozilla.org
  

The most important firefox extensions are:

• Console2
  
• Extension developer's extension. The 'reload all chrome' is useful for stuff that is otherwise cached.
  

To create the xpi file for publishing you need to change your chrome.manifest to point to the jar file (I keep another chrome.manifest for packaging in the repository so I can just copy it over). The ordinary manifest looks like this:

content     myextensionname      chrome/content/
skin        myextensionname      classic                 chrome/skin/
overlay     chrome://browser/content/browser.xul    chrome://myextensionname/content/browser_overlay.xul
locale      myextensionname      en                      chrome/locale/en/myextensionname/

and the packaging one looks like this:

content     myextensionname      jar:chrome/myextensionname.jar!/content/
skin        myextensionname      classic                 jar:chrome/myextensionname.jar!/skin/
overlay     chrome://browser/content/browser.xul    chrome://myextensionname/content/browser_overlay.xul
locale      myextensionname      en                      jar:chrome/myextensionname.jar!/locale/en/myextensionname/

I use these commands to create the jar and xpi:

cd chrome
zip -r myext.jar * -x \*.svn\*
cd ..
zip myext.xpi install.rdf chrome.manifest chrome/myext.jar

Python memcached

Installing the python bindings for the C libmemcached:

1. Patch libmemcache

It's been a while since I used patch, so I thought I'd record the command I used. This was a multifile patch, and it applies the patches to all the right files. How cool is that! The -p1 prunes off one slash of the path since my directory was different to the guys who made the patch.


patch -b -p1 -i libmemcache-1.4.0.rc2.patch



2. Compile and install libmemcache


3. sudo apt-get install python-dev


4. sudo python setup.py install


5. Download the actual memcached, compile and install


6. Use it (StringClient for strings, Client uses pickle for other types):



import cmemcache
a=cmemcache.StringClient(["127.0.0.1:11211"])
a.set('key', 'value')
a.get('key')

Port forwarding to a VMWare NAT-ed OS

I had the need to forward ports to a VMWare machine behind a VMWare NAT. VMware has some good instructions on how to do this. For a linux host you need to edit

/etc/vmware/vmnet8/nat/nat.conf

which is pretty self explanatory.

Openchange: Open source exchange server

I just heard about Openchange, which is a GPL version of MS Exchange server. I think it is awesome people are working on this. Samba, openchange, soon we will be able to replace the entire windows backend with linux without impacting user desktops :)