Handling command-line options with the preprocessor in Xcode

Question

I'd like to set the value of a variable in my Xcode project based on a command-line argument passed into xcodebuild.

For instance, I'd like to run xcodebuild -project MyProj.xcodeproj -alltargets -configuration Debug ENV=2 and have it set a string named "rootUrl" in my code.

I'm expecting something similar to the following in my code:

#if (ENV == 2)
static NSString * const rootUrl = @"staging.url.com";
#elif (ENV == 1)
static NSString * const rootUrl = @"dev.url.com";
#else
static NSString * const rootUrl = @"prod.url.com";
#endif

But no matter the value of ENV I pass into xcodebuild, rootUrl always gets set to "staging.url.com".

I also have ENV=$(ENV) set in my Preprocessor Macros under Build Settings.

How can I achieve the desired behavior?

Answer 1

Try replacing ENV=2 with GCC_PREPROCESSOR_DEFINITIONS="ENV=2" on your command line. I don't think you need to set the 'Preprocessor Macros' in the Build Settings as it will be overridden anyway.

See xcodebuild - how to define preprocessor macro? for more information.