All the Good Titles Were Taken - Chris Scott

Reloading OS X and Restoring from a SuperDuper Backup

Chris Scott — Wed, 07 May 2008 13:47:05 +0000

Last night, I decided to reload OS X on my MacBook. Contrary to most expert opinions, I upgraded to Leopard instead of doing a clean install. Since my performance has seemingly gotten progressively worse over the past six months, I figured a clean install was the way to go. Here’s what I did:

Did a full backup to an external USB drive using SuperDuper.
Did the above again to another drive just in case…
Left the USB drive attached and rebooted my MacBook while holding down the Option key to get the boot menu and chose to boot from the USB drive just to make sure everything was backed up.
Did the above again with the other drive just in case…
Disconnected the USB drive, inserted the Leopard DVD and rebooted while holding down the Option key again and chose to boot from the DVD.
Did the installation and customized the options to remove print drivers and language translations I don’t use.
Created the primary account on the new install the same as my current account.
Ran Software Update and rebooted until all updates were installed.
Enabled the root user.
Logged in as the root user and ran the Migration Utility.
Plugged the USB drive in and chose the option to migrate my data from a mountable volume and chose the USB drive and my user account. Chose the option to overwrite the current account.
Read a few chapters of a book while this copied.
Unmounted the USB drive and rebooted.
Logged in as my normal user account and verified everything still worked. It did.

You could probably skip having to enable the root user by creating a temporary user account during the installation and then telling the Migration Utility to just copy your account over since that wouldn’t require replacing the current account which requires you to be logged in as root.

I’m very impressed with how easy this was and that everything “just works” after the restore. If you’ve done this before and have any feedback, let me know in the comments.

Followinger: Making Twitter Follow Decisions Easy. Like Your Mom.

Chris Scott — Thu, 24 Apr 2008 02:55:16 +0000

Yes, that’s the best title I could come up with for my latest project Followinger. The idea is simple: follow the followinger user and then you can d followinger with a Twitter username and you’ll receive a d back with all kinds of fun stats:

when their account was created
how many people they are following
how many people are following them (friends)
the ratio of following to friends

The idea is that when you want to make a follow decision these stats are good to know. If you see that the account was just created or they follow way more people than follow them, you may want to think twice about following them back. This tool gives you a way to get this info in a Twitter reply.

Feedback welcome.

“Cryptography.CryptographicException: Bad Data” Exception Moving from .Net 1.1 to 3.5

Chris Scott — Fri, 18 Apr 2008 20:10:19 +0000

We just finished moving a few apps from .Net Framework 1.1 to 3.5. One of the problems we ran into was this exception when using some symmetric encryption code. When we decrypted the value from the DB, this was being thrown.

From what I can tell, it looks like in 1.1 passing null data to the decryption worked (or at least silently failed) and likely returned null back (well, a blank string in our case due to type conversion). However, in 3.5 this exception gets thrown.

An easy fix but one of those little things that took a while to track down so hope this helps someone.

Registration Open for BarCamp Orlando

Chris Scott — Thu, 28 Feb 2008 14:41:51 +0000

So why are you reading this? Go register!

Using jQuery and JSONP to Get AIM Status

Chris Scott — Fri, 25 Jan 2008 18:17:40 +0000

For a new site, I wanted to have a DIV’s background image be dependent on the online status of an AIM user. jQuery and the AIM Presence API make it easy.

First, the code:

$.getJSON("http://api.oscar.aol.com/presence/get?k=key&f=json&t=aimuser&c=?",
function(result){
if (result.response.data.users[0].state == ‘online’) {
$("#status").css("background-image", "url(’online.jpg’)");
}
}
);

Using the getJSON() method of jQuery, we pass in the URL of the AIM Presence service with the parameters needed.

The f parameter tells the service what format to return the results in–JSON in our case. The c parameter specifies the JSON callback to use–this is important! The k and t parameters specify the AIM key to authorize the request and the user to query the prescense for. Note that key and aimuser need to be replaced with your AIM key and the user you want to query if you’re playing along at home.

The second parameter we pass in to getJSON() is the function we want to use to process the JSON data that gets returned. In this case, my CSS rule for the #status DIV specifies the background image used by default which is the offline status. This way, if there is a problem with the service or API, we default to it being offline. So, the function here just checks the first member of the returned users array in the response and compares their state to the string 'online'. We only need to worry about the first user returned since we’re querying the status for only one user.

The important part of this is setting c=? in the parameters passed to the AIM Presence service. This tells jQuery to replace the ? with the correct method name to call and passes it in to the service. Without this, you’ll get 'invalid label' errors in Firefox and it just won’t work in other browsers. The jQuery getJSON() docs note this but it wasn’t clear to me from the example at first how to use it.

That’s all there is to it. One more reason to love jQuery!