Archive for the ‘code’ Category

Programmatically getting the CellID from your Windows Mobile phone

Wednesday, March 12th, 2008

I’m still on paternity leave at the moment, so time near a computer is limited to 20 or 30 minute periods in the rare occasions while Faith is asleep!

But in the last few days, I’ve still been playing with a few new geeky things. One of these is FindMe – a Windows Mobile application from Electric Pocket.

screenshot of FindMeThe basic idea is:

  • it gets the CellID of the GSM transmitter that your mobile phone is currently talking to
  • if it hasn’t seen this CellID before, it displays “You are in a new place” and prompts you to type in a name for where you are
  • if it has seen this CellID before, it uses the name you last entered for it

Then it uploads your name for the CellID (your description for where you are) to your Facebook profile.

Hey presto – location tracking without the need for GPS.

It works quite well.

I’ve played with location based stuff on my phone before but never tried to use GSM cell id before. I did consider it, but after failing to find a free database that could transform the cell id string into a location I could plot on a map, I didn’t really pursue it any further.

Playing with FindMe encouraged me to give it a try.

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Building C code for Windows Mobile

Saturday, February 16th, 2008

I was asked to get a C application working on Windows Mobile. Some colleagues at work have got some hobby code : a bunch of C files which they want to try out on a huge range of mobile platforms such as a slug. On Linux-based platforms, it’s apparently fairly straightforward – without too much work, gcc or some such compiler turns the code into a neat little executable.

Now the plan is to try it on a Windows Mobile device. And, probably cos I won’t shut up about Windows Mobile, they asked if I’d fancy giving the code a try on Windows Mobile.

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PowerShell: Providers vs Cmdlets

Tuesday, February 12th, 2008

When I wrote the PowerShell snap-in for WebSphere MQ, I chose to implement it as a set of cmdlets.

PS C:\> $myqmgr = Get-WMQQueueManager DALE
PS C:\> Get-WMQQueue -Qmgr $myqmgr

They are new commands for WebSphere MQ – commands that let you get, create, modify new objects representing WebSphere MQ objects.

The commands are consistent with existing commands in syntax and style, to be sure. But, they’re still new commands.

I didn’t have to do it this way.

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Cryptography with C# in Windows Mobile

Monday, February 11th, 2008

I wrote last week about an evening I spent throwing together a password manager for Windows and Windows Mobile. As I wrote at the time, one of the motivations was to try writing some encryption code.

I’ve finally got around to writing it, and wanted to post it here with a few comments.

This is what I needed code to be able to do:

  • Encrypt and decrypt data based on a user-provided password
  • Encrypt/decrypt consistently on both Windows desktops and Windows Mobile devices – a file encrypted on a Windows Mobile PDA should be able to be decrypted on a Windows desktop, and vice versa

The System.Security.Cryptography library in .NET makes this fairly straightforward – the class I have written to add crypto support to the password manager app needed only a few hundred lines of code in total.

I’ve shared a simplified version of the source at the end of this post.

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Donating for freeware

Thursday, February 7th, 2008

If I’ve ever talked to you about Windows Mobile, the chances are I’ve probably mentioned my wiki note-taking app. Of all of the bits of mobile code hacking that I’ve done, it is the one that (a) I dont seem to shut up about, and (b) has been one of my most popular*.

The app has been around for over a year now, and gets downloaded from about 1000 – 1700 unique IP addresses each month (Plus a few thousand more from mirrors on freeware sites).

The forum set up for users to report bugs and request features has over sixty active users.

And I generally get emails from 20 or 30 other people with requests each month who don’t want to use the forum for whatever reason.

I’ve even had emails from people using the app far more than I ever envisaged: people who are using the wiki as a work intranet wiki, installing a copy for each of their staff; people who use the wiki to maintain and develop websites; and more.

It would seem that there is an audience and a demand for this app.

Nearly a year ago, I decided to try a little experiment to see how this demand would translate into people prepared to pay for it.

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Writing a mobile password manager

Thursday, February 7th, 2008

I miss developing mobile apps. With the exception of the never-ending tweaks and revisions to my mobile wiki app, I’ve not done any mobile development in weeks. (Is it very sad that I missed it? 😉 )

Until tonight. Hurrah – back to playing with fun stuff.

One of the things I typically want to use on my phone is a mobile password manager – particularly as I do more web browsing on my phone, and mobile browsers like Pocket Internet Explorer and Opera Mobile don’t remember passwords.

I’ve tried several existing password managers – I’ve even paid for a couple, like eWallet (love the way it shows credit card details to look like a pretend credit card) and SplashID (always loved the desktop version). But I never found one that I really liked. At the moment, I’m back to storing passwords in a text file, and using mobile Notepad to access it.

There were problems with all of them…

One-handed or stylus-free navigation is bad – Teeny-tiny controls. Drop-down lists that you need to not only touch the screen to open, but then scroll up and down in. Basically, take a look at a design doc like this and do the opposite of pretty much everything 🙂

Too many clicks/presses to get to a password – SplashID for example: to get a website password, you touch the screen to open the category drop-down list, touch the screen to scroll to the “Web Logins” category, scroll through the list to the website you want, touch the screen to select it, press the “Tools” button, then press “Unmask Fields”. Too much.

No clipboard access – Unforgivable, this one. I like to use randomly generated passwords where possible. Once you’ve used the fiddly controls, and gone through all the steps, you can see the password on the screen – hurrah! Can you copy it to the clipboard for pasting into a web form? Nope. Even Ctrl-C / Ctrl-X / Ctrl-V don’t work – and most apps at least leave that basic Windows clipboard support in. So you have to remember your password after reading it. And with my passwords, that’s a pain. I used to find a scrap of paper, and write it down to make it quicker to type back in. So secure(!)

Actually, to be honest, even after all that, the final straw that stopped me using SplashID was the fact that it’s sync plugin consistently hosed my ActiveSync. Not only would it not sync, but it’d crash ActiveSync and stop everything else from syncing too. The day I uninstalled SplashID, my phone became a million times more useful from that alone!

This was all enough of an excuse to try throwing together my own password manager.

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Adding remote system admin support to PowerShell (before PowerShell V2)

Thursday, January 17th, 2008

Jeffrey Snover of Microsoft has written a very interesting post on PowerShell cmdlet development, prompted by the release of my latest updates to the WebSphere MQ PowerShell cmdlets.

By way of background, the cmdlets let you administer WebSphere MQ from the Windows PowerShell command prompt and scripting environment. One of WebSphere MQ’s biggest strengths is the breadth of it’s platform support, so it was no surprise that one of the most requested features to be added to the cmdlet library has been to be able to use PowerShell with WebSphere MQ queue managers on non-Windows servers.

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Displaying constant names (rather than values) in PowerShell cmdlets

Wednesday, November 21st, 2007

I’ve mentioned before that I’m working on some PowerShell cmdlets for WebSphere MQ. I thought I’d pass on a few tips that I picked up this week on improving the usability of the information displayed by Get- cmdlets in PowerShell.

The easiest way to explain it is to demonstrate with an example:

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