Cppcon 2014 (The C++ Conference) September 7th – 12th Bellevue, WA, USA: schedule has been posted

A lot of readers have been curious about what conferences I attend.  I’ve attended many PDCs, C++ (going native), builds, MVP summits, and TechEd’s in the past.   I’ve even hit a couple of consumer electronics shows and Comdexes (I’m dating myself here) in the past.

A big new conference is being held this year in Bellevue, Washington, USA this year that looks pretty exciting.  The schedule of talks has been posted now at

http://cppcon.org/conference-program/

and the list of talks looks amazing.   There are well over a 100 talks going on.

Registration is still open at

http://cppcon.org/registration/

How to target XP with VC2012 or VC2013 and continue to use the Windows 8.x SDK

One of the limitations of the Microsoft provided solution for targeting XP while using Visual Studio 2012 (Update 1 and above), or Visual Studio 2013, is that you must use a special “Platform toolset” in project properties that forces usage of the Windows SDK 7.1 (instead of Windows 8.x SDK which is the default).  The other function the platform toolset provides is that it sets the Linker’s “Minimum Required Version” setting to 5.01 (instead of 6 which is the default).  But that function can just as easily be done manually by setting it in project properties.

So how about the first main function of the platform toolset?   Setting the platform toolset to one that targets XP does the following:

(1) Changes the Platform SDK being used from Windows SDK 8.x (8.1 with VC2013 and 8.0 with VC2012) back to Windows SDK 7.1

(2) Adds a preprocessor define:  _USING_V110_SDK71_ to the build

The second one turns out to be important, due to a piece of code in atlwinverapi.h, namely the following:


extern inline BOOL __cdecl _AtlInitializeCriticalSectionEx(__out LPCRITICAL_SECTION lpCriticalSection, __in DWORD dwSpinCount, __in DWORD Flags)
{
#if (NTDDI_VERSION >= NTDDI_VISTA) && !defined(_USING_V110_SDK71_) && !defined(_ATL_XP_TARGETING)
     // InitializeCriticalSectionEx is available in Vista or later, desktop or store apps
     return ::InitializeCriticalSectionEx(lpCriticalSection, dwSpinCount, Flags);
#else
     UNREFERENCED_PARAMETER(Flags);
     // ...otherwise fall back to using InitializeCriticalSectionAndSpinCount.
     return ::InitializeCriticalSectionAndSpinCount(lpCriticalSection, dwSpinCount);
#endif

As you can see, if we do not use the platform toolset that defines _USING_V110_SDK71, i.e we don’t use the Windows SDK 7.1, then we don’t get the benefit of avoiding a call to InitializeCriticalSectionEx, which is a function only available on Vista and above.  This will cause your binary to not load on XP.

But what if we really want to use the Windows 8.x SDK (taking care, of course, that we don’t call any Windows 8.x functions directly, to keep support for older operating systems). Why would we want this? For example, we may want a structure definition, some preprocessor define, or function declaration, i.e. we may want to support some feature of Windows 8.x if actually running our app on that OS.

Say we’ve decided to use Windows 8.x SDK while still allowing our app to run on XP. Are there any options available? i.e. can you keep using the v110/v120 toolsets instead of the v110_xp/v120_xp toolsets? Yes, it turns out that Microsoft left a nice loophole in the code to do exactly that. Notice the mysterious define in the block of code above named _ATL_XP_TARGETING. Turns out this is an alternative way to support XP targeting while _USING_V110_SDK71_ is NOT defined. So if you really want to support XP while using Windows 8.x SDK, we simply need to ensure our code is built with _ATL_XP_TARGETING defined. The easiest way to do this is to add a /D_ATL_XP_TARGETING flag to our C/C++ command line options in project properties.

Then, the only other step is to set the “Minimum Required Version” in project properties under Linker – System to 5.01, and we’re all set - a simple way to target XP and still use the Windows 8.1 SDK without using the platform toolset that Microsoft provided to target XP.

In summary, the _ATL_XP_TARGETING define, while undocumented, is an interesting way to keep support for XP while also allowing continued use of the Windows 8.x SDK (rather than being forced to be permanently stuck on  the older Windows 7.1 SDK)

Was forbidding desktop applications on Windows RT the correct move?

Every day, someone bugs me at work about the news reports relating to how the Surface RT was not the success Microsoft had hoped it would be.  And Asus had the same conclusion.   I tell them Surface RT was a great piece of hardware.  It had the misfortune of not being able to run desktop apps.

But what about if Windows RT (Windows ARM) had allowed desktop applications (that have been recompiled to use the ARM instruction set) to run instead of just the ones that Microsoft had allowed (i.e. Office, and several built in apps, such as notepad, calculator, and some remote debugging tools).

I’ve been following the threads on xda developers on how the digital signing of desktop apps was circumvented to allow desktop apps to bypass this check completely, and in effect, open it up for desktop development.

Apart from the exploit, how was this possible at a tools level?  Well, if we go back to //build (in 2011), and look at the Beta version of Visual Studio 2012, you’ll notice something interesting: a complete version of MFC for ARM (including static lib files).  You’ll also notice that several key Windows SDK libraries were excluded (such as common controls, etc), making these MFC libraries more difficult to take advantage of.

The question remains: why would they have included MFC if they hadn’t planned on allowing developers to make desktop apps targeting ARM? My theory is that the original plan was to allow development of desktop apps for ARM, but at some point it was decided that desktop apps should be controlled and their creation only made available to Microsoft themselves.  Hence, when the first developer preview came out at //build there were still remnants of the original plans.

After this first build, subsequent builds removed the MFC libraries that were included in that first Beta.

So coming back to the original question: was forbidding desktop apps on ARM the correct move? At the surface level (pardon the pun) it looks to be a good decision.  the WinRT (Metro) environment provided for store apps, is tightly controlled, and therefore can have a better impact on battery life, potential viruses, app revenue, etc.  But it does stifle competition.  Look at VLC for ARM right now.  They can’t make a desktop app so have been forced to go to kickstarter to fund a Windows 8 (Metro) version of their app.  It’s still under development due to the tight controls over which APIs are allowed in WinRT apps. It’ll be interesting to see when, if ever, they release something.

Imagine the ability to have Chrome or Firefox for your Surface RT? Good thing?  I’m not sure.  Or your favorite app, which only needs to be recompiled for ARM using Visual Studio, and released directly from the software developer rather than through the store.  Good thing?  Hmm, the pros and cons are hard to weigh.  If you are starting from a zero ecosystem and trying to build it up, maybe desktop apps would have been a good thing.  But on the other hand it might have caused developers to focus less on the Windows Store apps and more on their legacy desktop apps.

But judging from the developer buy-in for WinRT (Windows Store apps), it’s a moot point.  The fact is, there hasn’t been enough buy-in.  And this is the key to success of the ecosystem, having developers risk getting no revenue from a store app, vs continuing with their legacy desktop apps on Intel only.  If they had allowed desktop apps on ARM, it’s possible more of those developers would be more excited about Windows RT.

New in Windows 8.1 store apps: a way to separate your app from your resources

One of the biggest complaints about the Windows 8 Windows store app approach to dealing with localization (separate translations for each language you decide to support), was the inability to decouple the various localizations from the main app.

As I’ve talked about in previous blog posts, the satellite DLL approach to Windows desktop apps, is an excellent one that can be used successfully with a lot of manual work (and can be automated quite easily when targeting Vista and above platforms).  But in Windows 8 store apps, there was no real analogy to this.

Windows 8.1 introduces a new type of package, a resource package.  MSDN describes it well here, I’ll provide a brief summary:

A resource package is a subset of your app that is used to provide language, scale, and DirectX features.  When you deploy an app to a machine, the decision is made whether you need one or all of the resource packages.  The app package itself can be deployed to a user’s machine with none of the resource packages, one of them, or all of them, depending on the particular needs of that machine. This is great for 2 reasons: it potentially increases download speed and reduces disk space.

An app bundle manifest (.appxbundlemanifest) is what describes your app’s package and all its resource packages.

The great thing about this new system, is that Visual Studio 2013 automatically handles this for you (separates the resources into separate resource packages).

There is also a package API that allows you to get information about packages, and a sample has been prepared by Microsoft and is found here:

http://code.msdn.microsoft.com/windowsapps/Package-sample-46e239fa

as well as another great sample that shows you how this resource package approach could be used in a game:

http://code.msdn.microsoft.com/windowsapps/Games-with-resource-62bd72aa

If you’re ok with targeting Windows 8.1 for a future Windows Store app (see previous blog posts on pros and cons of targeting Windows 8 vs Windows 8.1), this is an excellent new system that I believe will be a great boon for developers.

A note about Stroustrup’s The C++ Programming Language 4th Edition

As far as C++ books are concerned, this is the definitive reference, from the inventor of C++, Bjarne Stroustrup.  I grew up with his 2nd, 3rd, and Special Editions, and I highly recommend that you take a look at the 4th for its great C++11 content.

Now, I don’t recommend you buy it right away.  Yes, I know you may be surprised by that statement, but let me explain. Stroustrup is one of those authors that takes accuracy seriously.  Due to that, he tends to go through many “printings” of his books.   He makes changes (corrections) in each of these printings, based on reader feedback.

Take a look at the errata for his 3rd and special editions:

http://www.stroustrup.com/3rd_errata.html

He went through 21 revisions of the 3rd edition, and 14 revisions of the special edition (which was basically a continuation of the 3rd edition, except in hard cover).  So a total of 35 different 3rd editions when you include the special editions (disclaimer: some of these overlapped, i.e. there were early special edition printings equivalent to 3rd editions in higher printings, but you get the idea)

Why am I mentioning this?  Because the 4th edition is very young.  He’s already up to the 3rd printing after a couple of months:

http://www.stroustrup.com/4th_printing3.html

Also, complaints have been made about the flimsy (physical) nature of the original release of the 4th edition.  Yes, it’s a paperback.  However, it looks like Addison-Wesley has heard the complaints because a hardcover version of the book will be released on July 29th!

So I recommend you take a look at buying the hardcover version after a few months of revisions.  You’ll have the majority of “big” fixes, and then you can follow along the errata pages for future fixes.

How do you know what printing you’re going to get if you order from somewhere online?  It’s hard to know, you could get a very early one based on stock. But amazon tends to go through stock quickly.  Another thing you could do is to get one from your local bookseller, and take a look on the inside to see what printing you’re getting.

Visual Studio 2013 support for targeting Windows 8

I’ve been working my way through the multitude of //build 2013 session videos on channel9, and I came across an interesting presentation:

Upgrading Windows 8 Apps to Windows 8.1

There is a lot of really great information about the gotchas for deciding on making an app that is specific to Windows 8.1.

The main point you need to remember: once you make your app target Windows 8.1 (e.g. by converting to an 8.1 app and taking advantage of 8.1 specific APIs), your app will not run on Windows 8.  On the other hand, if you target Windows 8, your app will run under both Windows 8 and Windows 8.1

Here’s the kicker: Visual Studio 2013 will NOT support creation of new Windows 8 store apps, you’ll only be able to create Windows 8.1 store apps.   However you will be able to edit and build existing Windows 8 projects with Visual Studio 2013.

So if you want to continue to target Windows 8 when creating new store apps, you are going to need both Visual Studio 2012 and Visual Studio 2013 installed. You’ll really only need Visual Studio 2012 to create the project, and once it’s created you can switch over to Visual Studio 2013.

This seems to me to not be a technical limitation, but more of a way to encourage developers to target Windows 8.1 from the get go if creating a new app.

To me it would make more sense to support creating Windows 8 store apps in Visual Studio 2013, since the infrastructure is already there to continue to edit and build existing Windows 8 projects.

Going Native 2013 C++ conference – new discount for first 50 people!

The Going Native 2013 conference is taking place this September 4-6, 2013 in Bellevue, Washington.

50 lucky people can register now for Going Native 2013 – Use promo code: $100dGN13 to receive a US$100 discount.

Note: this code may cease to work at any time, once the 50 spots are filled, it goes back to the regular price.

I personally can’t wait for this conference, the first one last year was quite special, and they’ve extended it this year for one extra day.