XCODE 错误：未构建新文件

Question

So first I made a new project by going to File> OS X > Command Line Tool and chose C as the language. This is what I got:

Then I made a new C file called program.c:

Then I pressed run. It didn't build successfully:

However, when I deleted the first default file (main.c) and then pressed run program1.c....it built successfully.

My problem: Why can't I have several files under the same project and run them successfully?

Answer 1

You can't have 2 main functions

Edit: each c program has to contain only one main function. Other files of that program can not implement another main function.

Answer 2

Because you will have the main function declared in both files. I do not know how to tell XCode to build two separate applications..