Some people might want to avoid having to learn Xcode to get started programming with Objective-C. If you’re used to using the UNIX shell and command-line tools, you might want to edit, compile, and run your programs using the Terminal application. Here, we examine how to go about doing that.
Before attempting to compile you program from the command line, make sure that you have Xcode’s Command Line Tools installed on your system. Go to Xcode, Preferences, Downloads, Components from inside Xcode. You’ll see something similar to Figure 2.10. This figure indicates that the Command Line Tools have not been installed on this system. If they haven’t, an Install button will be shown, which you can click to install the tools.