Can I pass a preprocessor definition to the resource compiler through the command line?

Question

I'm currently trying to switch between a few different default Icons in a Visual C++ .rc file using #ifdef tags.

The builds switching the #define value are being created through command line using MSBuild.

The difficulty I have been running into is that using Visual Studio 2010, in order to pass a preprocessor definition to the resource compiler you must define it in the project settings (Config Properties -> Resources -> General).

This makes it difficult to use an #ifdef tag because using this method it will always be defined in the resource compiler.

I would love to define it to a value, so that I might use a preprocessor #if SOMEVALUE == 4 might work, but Cannot seem to find a way to pass a Preprocessor definition + value to MSBuild via the command line.

Does anyone know a way to pass a preprocessor definition directly through to the resource compiler or a way to define a value for a preprocessor definition via commandline for msbuild?

Answer 1

Yes, this can be done.

Try using environment variables to pass values into your build process.

In your project properties add ;$(CMDLINE_DEFINES) to the end of your resource preprocessor definitions. (Be sure to pick the right configuration.)

Then when you use MSBuild from the command line type (or add to a batch file)...

C:\Projects\SomeProject> set CMDLINE_DEFINES=SOMETEST=42
C:\Projects\SomeProject> MSBuild SomeProject.vcproj

A batch file may look like:

@echo off
SET CMDLINE_DEFINES=%1
MSBUILD SomeProject.vcproj

Using this batch file, whatever you pass on the commandline will be passed on to the build process as your preprocessor macro(s).