Hi COM! How’s it going?

In June 2000 at PDC in Orlando Microsoft announced .NET Framework project. Shortly after that developers concentrated around products and technologies made by Microsoft started debate on what’s the future of software development. One of questions and quite obvious was: So does this mean that COM is dead?. A few months later, Don Box addressed that concern in his extensive article Is COM Dead?:

It depends on what your definition of COM is. COM is many things to many people. To me, COM is a programming model based on integrating components based on type. Period. This was COM’s primary contribution to the field of component software, and that contribution has changed the way millions of programmers build systems today.

Don is right and the answer is historically and technically correct, however this is an indirect answer that didn’t cheer up at all. Given the closing words in that article:

(…) CLR provides significant benefits to developers who are using COM today. Virtually all aspects of the COM programming model have survived (…) I look at the CLR as breathing new life into the programming model that I’ve spent the last seven years of my life working with, and I know there are other programmers out there who share this sentiment.

overall conclusion becomes more an abstruse philosophy than binary answer. What about all these cryptic terms of Component Object Model technology made by Microsoft, like OLE, ActiveX, DCOM and other? Silent.

Nearly ten years later, developers are still asking the same question (a few days ago, similar discussion took place on ACCU mailing list) about COM. Alf. P. Steinbach gave an interesting answer that, however, sounds very similar to the one given by Don Box:

COM is one of the few successful C++ component technologies, if not the only one (depending on one’s definition of “successful (…) Some reduced and slightly modified versions of COM are used in e.g. Linux user interface and in Firefox browser (XCOM). Original COM itself is however a Windows-specific technology. But while it’s necessarily used to interface to the operating system and at higher levels in e.g. scripting, it’s my impression that it’s now now not much used as a general C++ component technology, i.e., that use of COM is something forced, not something desired and freely chosen.

Even though both are similar, it’s been decade since the question was asked for the first time and now we have 10 years of experience based on observations what has changed after .NET was thrown on the marked. The managed baby seems to be winning the market of Microsoft-oriented (not only, though) developers and users. COM is widely used as components of Windows systems and other already existing software but are new COM servers and objects still being developed? Or, has it started to suffer of COM programmer species extinction?

The www.microsoft.com/COM/ website confirms that:

Microsoft recommends that developers use the .NET Framework rather than COM for new development.

In my humble opinion, Mr. COM is like an old veteran, alive, but most of his comrades-in-arms have died, so he usually goes to pub alone.

Visual C++ Toolkit 2003 still in use

Charles Petzold's TattooIn 2004, Microsoft published Visual C++ Toolkit 2003 – full version of Visual C++ 2003 optimizing compiler (version 1310) available free of charge. It was the first free, good and almost complete implementation of C++ programming language by Microsoft. It is quite old but still used by many developers.

The Toolkit is fairly complete, but you can not avoid a few hacks if you want to use it :-) So, I’ve decided to collect them all in one place to help building projects like GEOS, libLAS or GDAL/OGR with the Visual C++ Toolkit 2003.

Installation

First, installation of the following packages is required:

  1. Microsoft .NET Framework SDK 1.1
  2. Microsoft Platform SDK for Windows Server 2003 R2
  3. Microsoft Visual C++ Toolkit 2003 (no longer available from Microsoft website, just be persistent cuiling for it)

Hacks

This is list of hacks like installation of missing components and fixing a project makefiles:

  1. The .NET Framework SDK 1.1 installation (listed above) is required in order to get C Run-Time libraries installed: msvcrt.lib and msvcrtd.lib. The .NET SDK installer will copy these files (and a few other components) to directories located in:

    C:\Program Files\Microsoft Visual Studio .NET 2003
    
  2. Surprisingly, import library for C++ Run-Time Library msvcp71.dll is not included in the Visual C++ Toolkit 2003 distribution. Missing files can be downloaded from CERN server: msvcprt.lib and msvcprt.def. Copy them into

    C:\Program Files\Microsoft Visual C++ Toolkit 2003\lib
    
  3. The Toolkit does not include lib.exe utility – Microsoft Library Manager. Fortunately, lib.exe is just a simple wrapper on Microsoft Incremental Linker – link.exe. So, in your NMAKE makefiles replace lib.exe (or lib) command with:

    link.exe /lib
    

    Alternatively, you can build custom lib.exe wrapper using lib.c program. Recently, I’ve fixed NMAKE makefiles of GEOS (r2190) and libLAS (r876) projects using the former option.

Environment

Most of articles about Visual C++ Toolkit 2003 and Platform SDK installation procedure suggest to permanently update environment variables like INCLUDE, LIB and PATH. Personally, I don’t like this approach. Instead, I write a simple SET_MSVC71.BAT script which I execute in console window before I run NMAKE to build a software project using Visual C++ Toolkit 2003.

The script I use consists of three commands:

@echo off
CALL "C:\Program Files\Microsoft Platform SDK for Windows Server 2003 R2\SetEnv.Cmd"
CALL "C:\Program Files\Microsoft Visual C++ Toolkit 2003\vcvars32.bat"
CALL "C:\Program Files\Microsoft.NET\SDK\v1.1\Bin\sdkvars.bat"

Copy this script to location that is available from the PATH.

Sample build – libLAS

Below, a few simple steps are presented of using Visual C++ Toolkit 2003 and environment configured as presented above to build libLAS project. The same procedure should work for projects like GEOS or GDAL/OGR.

  1. Run Command Prompt (cmd.exe)
  2. Configure environment by executing SET_MSVC71.BAT script:

    C:\> SET_MSVC71.BAT
    

    Check if basic commands are available: cl.exe, nmake.exe, link.exe.

  3. Go to libLAS source code directory:

    C:\> cd dev\liblas\trunk
    
  4. Run NMAKE command to build libLAS library and utilities:

    C:\dev\liblas\trunk> nmake /f makefile.vc
    

Good luck!