The Wiert Corner – irregular stream of stuff

Jeroen W. Pluimers on .NET, C#, Delphi, databases, and personal interests

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Archive for the ‘Delphi’ Category

Debt in IT and Software Development (via: Coding Horror: Paying Down Your Technical Debt)

Posted by jpluimers on 2012/04/04

Debt and flood insurance

Thanks to Randy Glasbergen for the debt image

I love this quote from Jeff Attwood on technical debt in 2009:

periodically pay down your technical debt

and the Computer Weekely article about half a year ago:

Short-term speed may come at the price of long-term delays and cost.

Lately, I find that I need to explain Debt in relation to IT and Software Development more and more often.

We now all know what happens with the financial system when we let debt get out of control.

The same holds for your IT and Software Development.

Debts get introduced by not “playing by the rules”. The quotes are there because you can not always play nicely, and the rules are not always clear or known.

Lets give a few examples of rules that – from experience at clients – are more often than not neglected. The examples are based on Windows, but could just as easily be Mac OS X, Unix, OS/400 or anything else.

  • Make sure you use a recent Windows version
    I often see companies lagging more than one version behind (i.e. still use Windows XP or SQL Server 2000). That’s too far.
  • Don’t run your users with too many privileges (and certainly not as Administrators)
    Especially running as Administrator will get you in trouble with User Account Control (UAC) in Windows Vista and up.
  • Using directories like C:\TEMP is a no-no.
    This should be a no-brainer, but truckloads of in-company software still thinks it can write everywhere.
    I know C:\TEMP used to be the Temporary Folder some 20 years ago.
    But that was then, and this is now: Use the %TEMP% environment variable or GetTempPath function (even better: the GetTempFileName function or the .NET Path.GetTempFileName function).
    More in general for known folders, use CSIDL or KNOWNFOLDERID whenever possible. Your favourite development tool usually has a library functions for that, for instance the .NET System.Environment.GetFolderPath function.

These few were examples ranged from technically very broad to specific. There are more, but these will give you a rough idea how wide the field of debt can be. Even debt outside the realm of Technical Debt can turn out to be really expensive.

Every time you  postpone or skip a Windows version, you collect some debt in the hope (often wrongfully called expectation) that you earn more on the money/resource you just didn’t invest and putting that money/resource to use otherwise. The same holds for any other kind of debt.

The main problem with debt is not the total of the debt, it is the interest rate that makes the accrued debt grows faster than most people and organizations realize.

This is actually one of the main causes of the current world wide financial crisis, the same holds for many IT debts.

And for all kinds of debts, you often don’t know how high the interest rate will be, so the accrued value can be way beyond what you expect.

I’ve regularly seen projects collecting so much debt, that migration costs raised to thousands of hours because of it, resulting into management taking another very bad decision: rewriting the stuff from scratch. Don’t do that: Joel on Software excellently describes what happens when you do that.

What to do about it?

You might say “don’t collect debt”, but you can’t always avoid debt.

So you need to build periods where you pay off accrued debt. And you need to do that regularly, in order to avoid the interest pitfall.

This does not limit itself to software development (though that’s what I normally focus at). It covers a wide range of IT topics.

Sometimes, you can even pay your debt in advance. For instance, I was among the first to switch from Windows XP to the x64 of Windows Vista. I knew it would cause pain, but it immediately payed back by being able to use much more memory, and run more Virtual Machines at the same time. That made me more flexible and productive.

–jeroen

via: Coding Horror: Paying Down Your Technical Debt.

Posted in *nix, .NET, Delphi, Development, Opinions, Power User, Software Development, Technical Debt, Windows, Windows 7, Windows 8, Windows Vista, Windows XP | 9 Comments »

naming – What’s the use/meaning of the @ character in variable names in C#? – Stack Overflow

Posted by jpluimers on 2012/03/28

Duh, I always thought @ could only be used for strings.

Not so: just like with the & in Delphi is used to escape keywords, the additional use of @ in C# is to escape identifiers:

The prefix “@” enables the use of keywords as identifiers, which is useful when interfacing with other programming languages. The character @ is not actually part of the identifier, so the identifier might be seen in other languages as a normal identifier, without the prefix. An identifier with an @ prefix is called a verbatim identifier.

–jeroen

via: naming – What’s the use/meaning of the @ character in variable names in C#? – Stack Overflow.

Posted in .NET, C#, C# 2.0, C# 3.0, C# 4.0, Delphi, Development, Software Development | Leave a Comment »

“Cannot navigate to definition” annoyance in Visual Studio 2010 – (did it implement the mouse equivalent to Delphi code browsing? No, it didn’t)

Posted by jpluimers on 2012/03/08

This use case drove me nuts in Visual Studio 2010 for a while, but can be solved.

Use cases:

  1. Cannot navigate to definition.double click on a word to select it
  2. press Ctrl-C to copy the selected text
  3. result is either of these two dialogs:

    ---------------------------
    Microsoft Visual Studio
    ---------------------------
    Cannot navigate to definition.
    ---------------------------
    OK
    ---------------------------

    Cannot navigate to definition. The cursor is not on a symbol.or

    ---------------------------
    Microsoft Visual Studio
    ---------------------------
    Cannot navigate to definition. The cursor is not on a symbol.
    ---------------------------
    OK
    ---------------------------

The reason is that Visual Studio 2010 still thinks I am clicking the identifier (which I’m not, I just released the mouse button) while pressing the Ctrl key. Read the rest of this entry »

Posted in .NET, Delphi, Development, Keyboards and Keyboard Shortcuts, Power User, Software Development, Visual Studio 2010, Visual Studio and tools | Leave a Comment »

Anyone with a C#, Delphi or FreePascal implementation of the PRESENT Ultra-Lightweight Block Cipher encryption?

Posted by jpluimers on 2012/03/06

A short while ago a paper got published on PRESENT: An Ultra-Lightweight Block Cipher by Andrey Bogdanov et al becoming ISO standard 29192-2:2012.

Is there anyone that has a C#, Delphi or FreePascal implementation with unit tests?

–jeroen

Posted in .NET, C#, C# 2.0, C# 3.0, C# 4.0, C# 5.0, Delphi, Development, Software Development | 13 Comments »

P/Invoke: usually you need CharSet.Auto (via: .NET Column: Calling Win32 DLLs in C# with P/Invoke)

Posted by jpluimers on 2012/02/28

I don’t do P/Invoke often, and somehow I have trouble remembering the value of CharSet to pass with DllImport.

In short, pass CharSet.Auto unless you P/Invoke a function that is specific to CharSet.Ansi or CharSet.Unicode. The default is CharSet.Ansi, which you usually don’t want:

when Char or String data is part of the equation, set the CharSet property to CharSet.Auto. This causes the CLR to use the appropriate character set based on the host OS. If you don’t explicitly set the CharSet property, then its default is CharSet.Ansi. This default is unfortunate because it negatively affects the performance of text parameter marshaling for interop calls made on Windows 2000, Windows XP, and Windows NT®.

The only time you should explicitly select a CharSet value of CharSet.Ansi or CharSet.Unicode, rather than going with CharSet.Auto, is when you are explicitly naming an exported function that is specific to one or the other of the two flavors of Win32 OS. An example of this is the ReadDirectoryChangesW API function, which exists only in Windows NT-based operating systems and supports Unicode only; in this case you should use CharSet.Unicode explicitly.

–jeroen

via: .NET Column: Calling Win32 DLLs in C# with P/Invoke.

Posted in .NET, Ansi, C#, Delphi, Development, Encoding, Prism, Software Development, Unicode | 3 Comments »

FireMonkey and (OS X, iOS, Windows) Link Clearance

Posted by jpluimers on 2012/02/21

Some links that I found useful for doing FireMonkey and development for OS X or iOS:

–jeroen

Posted in Delphi, Development, FireMonkey, OS X FMX, Software Development | 2 Comments »

Jason Southwell (from arcana) just published DuckDuckDelphi: a unit to do Duck typing in Delphi XE2 (not XE)

Posted by jpluimers on 2012/02/16

If you haven’t seen Jason announce this in the general Delphi 3rd party newsgroup or his announcement thread on the FaceBook Delphi Developer group yet, this is a definitive must read:

Jason Southwell (from arcana) just published DuckDuckDelphi: a unit to do Duck typing in Delphi XE2 (not XE):

Duck Duck Delphi

DuckDuckDelphi is an Open Source (MIT License) unit for Delphi XE2 which adds duck typing functionality to a normally strongly typed language.

Great stuff that makes a truckload of my code so much easier to maintain.

–jeroen

via arcana – DuckDuckDelphi.

(Edit: 1400 UTC+1 Sorry, wrong boolean; wrote “and” but should be “not” XE).

Posted in Delphi, Delphi XE2, Development, Software Development | 8 Comments »

There is a great Android Design – UI Overview site, but no great UI design tools for Android

Posted by jpluimers on 2012/02/15

Recently the Android Design site was launched with great explanation on how to properly design UIs for Android Apps.

Like Apple’s iOS Human Interface Guidelines and Microsoft’s User Experience Design Guidelines for Windows Phone they are a must for any mobile developer.

Together with sites like Android UI Design Patterns, and mockup stencil tools, more Android UI mockup sketch tools and stencils allow you to give prospective users an impression on how an app might be looking like when developed.

What is lacking is a set of real Android GUI design tools. The kind of tools like the Xcode Interface Builder for iOS, or Expression Blend for Windows Phone that – together with iOS PSD templates or Windows Phone design templates (and more templates) – give you a killer start.

Also note Delphi XE2 that has a great UI designer which has consistently covered Windows UI design for 15+ years, including multi-touch and gesture support, and now covers Mac OS X and iOS for HD and 3D apps (but not yet with multi-touch or gesture support).

The only design tool for Android I could find is DroidDraw that emits the XML needed for Android UIs. It is painfully slow and lacks basic things like a property window to edit properties of UI elements.

Given the number of Android app developers, there is much room for improvement.

  • Am I missing something here?
  • What kind of tools are you using?

–jeroen

via: Android Design – UI Overview.

Posted in .NET, Android, Delphi, Development, iOS Development, Mobile Development, Software Development, Windows Phone Development | 6 Comments »

great answer by Remy Lebeau on windows – CreateProcessAsUser doesn’t work when “change user” – on Stack Overflow part of @StackExchange

Posted by jpluimers on 2012/01/10

You might wonder why I quoted two great StackOverflow answers recently. Well, it is because I absolutely love the way that StackExchange.com and StackOverflow.com changed how to find quality answers (and questions!) on topics varying from programmers through Cooking to Chines Language Usage in a community based way.

This one is by Remy Lebeau, who is part of TeamB:

You don’t need to enumerate running explorer.exe processes, you can use WTSGetActiveConsoleSessionId() instead, and then pass that SessionId to WTSQueryUserToken(). Note that WTSQueryUserToken() returns an impersonation token but CreateProcessAsUser() needs a primary token, so use DuplicateTokenEx() for that conversion.

You should also use CreateEnvironmentBlock() so the spawned process has a proper environment that is suited to the user account that is being used.

Lastly, set the STARTUPINFO.lpDesktop field to ‘WinSta0\Default’ instead of nil so the spawned UI can be made visible correctly.

I have been using this approach for several years now and have not had any problems with it. For example:

… code sample is in the answer …

–jeroen

via: windows – CreateProcessAsUser doesn’t work when “change user” – Stack Overflow.

Posted in Delphi, Development, Software Development | 2 Comments »

Great answer by Cosmin Prund: How and when are variables referenced in Delphi’s anonymous methods captured? – Stack Overflow

Posted by jpluimers on 2012/01/05

Every once in a while, by accident you stumble on a really great answer on StackOverflow.

Here is a quote from Cosmin Prund describing on how Delphi implements anonymous methods using a TInterfacedObject descendant:

When you have a function like the one in the question, where you have an anonymous method accessing a local variable, Delphi appears to create one TInterfacedObject descendant that captures all the stack based variables as it’s own public variables. Using Barry’s trick to get to the implementing TObject and a bit of RTTI we can see this whole thing in action.

Read his full answer for the complete description including sample code.

I stumbled on this great answer trough the question Is it possible for a managed local variable to transparently “travel to” another local scope? which might sound like an odd question, but it is not: StackOverflow is about learning, and some people do that by asking questions on solving problems in a very uncommon way, just to learn there are far better ways of obtaining what they want.

–jeroen

via: How and when are variables referenced in Delphi’s anonymous methods captured? – Stack Overflow.

Posted in Delphi, Development, Software Development | Leave a Comment »