Clemens has a security patch for dasBlog.

Sheesh another nerd post.  I thought this might be useful information for the community.

If you're using multiple threads in the execution of an ASP.net page, don't count on Response.End() to do what you think it might do.  Looking back it's pretty intuitive, I just didn't think about it.

At work, we have some pages that can take several minutes to execute.  They can pull millions of rows from the database and process them and do all kinds of craziness.  As a result, users don't like to sit around and watch Internet Explorer's progress bar decieve them time and again.  I implemented a progress mechanism to let the user know what is happening.  I went through several iterations before I come up with something really easy to work with.  It's completely transparent to the developer, and allows them to “push” progress messages onto a stack (using the wonderful “using“ statement), which is rendered for the user at an interval during the lifetime of a page.  It preserves the behavior of postbacks and Server.Transfers, but does break redirects if they happen after the progress gets started (which I hardly ever do).

Anyway, the point of the story is to tell you about Response.End.  The progress updating happens on a worker thread from the ThreadPool.  When I implemented it, I thought it would be nice to detect if a user has closed the browser or hit stop.  Then we could save some resources if no one is listening anymore.  So, before updating the progress, I do a Response.IsClientConnected, and if they aren't, I was calling Response.End().  This seemed to work at first, because it does do something, the problem is it doesn't stop what's going on in the main thread.

Reflector (the most useful CLR tool ever) reveals that Response.End() is basically just calling Thread.CurrentThread.Abort(), along with doing some clean-up and such.  Notice the CurrentThread...oops.  All I was doing was ending my progress rendering thread.  Like I said, it makes perfect sense now.

So, what do you do about it?  Well, I'll come up with something.  It shouldn't be too hard, but it will be pretty specific to my situation, so there's no real universal answer, unless Microsoft were to change the implementation so that it was keeping track of the threads and killing the main one, although then my worker threads wouldn't die.  Chances are if you've implemented some kind of multi-threading in your ASP.net pages, you can figure it out.

I'll forever chuckle when I read that title.  Maybe you will too after you read this.

I was aware of the Nullable generic struct in the 2.0 CLR, but I only just now figured out that they've built direct support for it into C# 2.0.  This is awesome!  At work, we currently have a whole bunch of structs that add null support to the value types in the CLR.  So we have NullableSingle, NullableDouble, NullableUInt64, etc.  This helps us incredibly to match the database concept of numbers and such that can have null values.

I've been looking forward to Nullable for some time, but now I'm absolutely ecstatic about the C# support for it.  Using the magic question mark, I can declare a value type to be nullable.  For instance:

bool? hasHairOnHead = false;

Now you get the title joke, right? This means that hasHairOnHead can be set to null, not just through Nullable's HasValue method, but by actually setting it to null:

hasHairOnHead = null;

Freaking awesome, eh?  So now, the Headless Horseman's hasHairOnHead value can more accurately express his status. (OK, it was the first example I thought of).  The same goes for null comparisons and such!

Of course now I'll get confused reading documentation...Is that a question or a nullable type?  Just try to decipher this faq: Why don't nullable relational operators return bool? instead of bool?

That little question mark is going to save me alot of headaches.  Now I just have to wait for it to be out of beta. 

Today is Becky's birthday.  I'll refrain from revealing her age, as that would be detrimental to my health.  (She has a black belt in Kung Fu, you know)

I've been playing with the new membership framework in ASP.net 2.0.  The existence of this, and other nice things like the login controls are fantastic, but it really lacks the polish of other areas of the new framework.  Here's some constructive feedback:

The MembershipProvider looks like a pretty well designed base class, but it should implement more of its interface by default.  For instance, when creating your own provider, you're forced to implement Initialize, which configures the instance for the configuration in the web.config.  Initialize is defined in ProviderBase, but there should be a default implementation in MembershipProvider that at least configures the values for the required properties such as EnablePasswordReset and such.  I ended up using the Reflector to look at the AccessMembershipProvider to implement this method.  Also, the majority of the proeprties should have default implementations as well.

The documentation for implementing a MembershipProvider is also pretty inconsistent.  Some of the methods are supposed to throw exceptions for failures, some of them return booleans for success/failure (which I thought had been deemed not a good idea), and some of them say they should throw exceptions, but also return a boolean.

The MembershipUser class is also pretty good, but its ISerializable implementation is weird.  Deserializing one would leave it in an unusable state since its _Provider field would be uninitialized, and since it's not settable, its useless.

I love the idea and the ease of which you can use the membership concept. (The default “just works”) But to create the “pit of success”, there are some things to address and I hope someone is addressing them.

[UPDATE] Brad Abrams helped me get this feedback to the right people.  Thanks Brad.  It makes me feel really good about the direction of the .NET and Microsoft as a whole to know I can get my feedback to the people who need to hear it.  I may be making incorrect assumptions or drawing the wrong conclusions, but chances are if I am, then others are too.

The HD broadcast of the olympics just started...beautiful.  Just beautiful.

One weird thing though.  The audio keeps jumping from Dolby Digital 3/0 to 2/0 every few minutes.  I'm trying to figure out if it's a reception issue.  Anyone else having trouble?  If not, what are you getting?

[Update] I just went outside and unplugged all my cables except my cable modem and the livingroom connection.  I've got full Dolby Digital 3/2.1 now.  yeah!

The managed API for the windows performance counters is great.  It was just what I needed to track down some memory issues at work, and now I've got real-time information about what's going on.  It's much simpler than trying to use them with the old school api.  However, I need some more guidance on the usage pattern for creating and deleting the categories and counter definitions.  Are those things that should be part of an install/uninstall procedure, or should they be done on startup/exit of the program?  What kind of overhead should I expect in constructing/incrementing/disposing them?  The counters implement IDisposable, which makes me want to dispose them quickly.

Maybe some spelunking with the Reflector will shed some light.  I'll keep you posted.  In the meantime, feel free to share your experiences with performance counters in the CLR.

[Update] Duh.  I ran across System.Diagnostics.PerformanceCounterInstaller the other day.  Looks like that's how you should install them.  I love the installers as well.

I ran across the new web-based MSN Messenger the other day.  I haven't had access to messenger from work in a long time.  The old version didn't work through our firewall, so I developed a local proxy to tunnel the traffic.  Then they started blocking that traffic outbound.  Then they rolled out a crappy customized version of it to collaborate in-house which couldn't go outside the firewall.  But this web-based one works perfectly through the firewall, so I am once again available while at work...within reason of course.

Last night, I upgraded to XP service pack 2.  It went very smoothly.  The new wireless networking support is fantastic.  I can finally unload the annoying software that came with the laptop to manage the networks.

I'm a little dissapointed with the firewall.  It adds a few new features, but still doesn't seems as configurable as I'd like.  We'll see...some more time with it may change my mind.

It was a very simple, smooth install.  I would let any of my family or friends attempt it by themselves, and probably will.

I mostly finished up the work I started last week on the back wall of the house.  Thanks a bazillion to Mom and Dad for helping out.  A few things I did smarter this week were to use a heavy duty car jack to lift the heavy hardi-panel panels into place.  They are really heavy, and since they are about .5“ thick, they really cut into your hands.  The jack worked amazingly well.  Thanks to my co-worker Mark Leech for such an ingenious, yet somehow common sense idea.

I'll see about getting some pictures up later when I'm not so sweaty and tired.

Well, i just couldn't wait.  I played Peasant's Quest and won.  It was pretty fun.  I wonder if anyone got higher than 135.

In a comment discussion, I mentioned my disdain for using Perl for anything larger than simple scripts or line-based text parsing (which is what it was invented for...see below). I received some pushback on this opinion from Shelly, obviously from her own experiences with the language.  I enjoy pondering a dissenting opinion when based on experiences or data.  She says:

Using a good OO design and programming techiques, a perl program is not a nightmare for maintainability...just like any other language (yes even assembly).

Obviously, I need to open my mind here. I guess my question becomes: Once you get to the point where you need to apply OO design and programming techniques, are there not more suitable languages for a project like that?  I'm curious to know what other people's opinions are on this.  What are the advantages of Perl over other truly OO languages?  Why would you choose it instead of another language?

For your enjoyment, here's the original manpage for perl:

 NAME
  perl | Practical Extraction and Report Language

 SYNOPSIS
     perl [options] filename args

 DESCRIPTION
      Perl is a interpreted language optimized for scanning  arbi-
      trary  text  files,  extracting  information from those text
      files, and printing reports based on that information.  It's
      also  a good language for many system management tasks.  The
      language is intended to be practical  (easy  to  use,  effi-
      cient,  complete)  rather  than  beautiful  (tiny,  elegant,
      minimal).  It combines (in  the  author's  opinion,  anyway)
      some  of the best features of C, sed, awk, and sh, so people
      familiar with those languages should have little  difficulty
      with  it.  (Language historians will also note some vestiges
      of csh, Pascal, and  even  BASIC|PLUS.)   Expression  syntax
      corresponds  quite  closely  to C expression syntax.  If you
      have a problem that would ordinarily use sed or awk  or  sh,
      but  it exceeds their capabilities or must run a little fas-
      ter, and you don't want to write the silly thing in C,  then
      perl  may  be  for  you.  There are also translators to turn
      your sed and awk scripts  into  perl  scripts.   OK,  enough
      hype.

Ever pine for the days of 16 color, 160x120 resolution adventure games?  HomestarRunner.com has expanded its Trogdor-related franchise by adding Peasant's Quest.  Last week, they had this preview of it, which was also hilarious.  Becky loved the rabbit algebra line.  I just went through a couple of screens of the game here on my lunch break, and laughing my rear off (ouch).  Looks like you can save and everything.  I can imagine it would be the most fun to play with a friend.  Maybe I can play it with Dave sometime.

If you've never visited homestarrunner.com, start with the welcome and go from there.  Alot of stuff won't make much sense until you've meet the characters, which you can do from one of the hilarious main menus.  Strong Bad's emails are my favorite and have been the birthplace of many of the funniest things on the site, including Trogdor himself.  Enjoy.

[Update: fixed spelling of Strong Bad. I think String Bad should be a new character]

This week has been pretty crazy. While doing some routine caulk replacement in the master bathroom, I discovered some water damage behind the tiles.  After removing some tiles and discovering some nastyness, I decided I could get into the wall from the outside more easily to clean it out and repair damage.

That wall of the house is obscured by some thick bushes.  I pulled an old picture of the house so you could see. I cut the bushes back so I could get to it.  I then discovered that the panelling was pretty nasty near the bottom that was being obscured and I had some ant problems.

To make a long story short, I spent the weekend ripping off the outside wall and replacing it.  Andrew came down Saturday and helped me put the new panelling up.  It was that Hardi-Plank stuff that's more like concrete than wood, and was MUCH heavier than wood.  It was also difficult to cut.  It pretty much destroyed a saw blade with one cut.  But it's supposed to not ever rot or mildew or anything, so it should be worth it.

Andrew and I replaced the panels I had removed, and as you can see we actually removed the window.  It was in the shower and I was tired of people being able to see me take a shower.  Also, it was the source of the tiling problem in the shower that lead to the water damage and an ant infestation.  We'll be redoing the shower/bath over the next few weeks, and Becky is looking forward to that.

Thank goodness I hadn't removed more panels, or we would have died.  It's pretty hot outside.  The heat index is well over 100 degrees.  I also hit my thumb with the hammer way too many times. I just finished caulking the wall and thought I share what's going on.  There's still quite a bit of work to do.  I need to replace the remaing 2 panels, but I'll need some cooperation from the utilities to remove all the crap they've screwed into the wall on the outside.