I want to run the software Digital Datcom in my Mac, which is a Macbook Pro with macOS Mojave 10.14. For this I had to download the program Xcode form the appstore, as well as the gfortran package from the official page. I have already run the file datcom.f in the terminal with the command gfortran before, after that the instructions at the official page of datcom says that the program will start after typing "datcom" one more time but my terminal says me that the command does not exist. Can anyone tell me please what I need to do to run the program and reach the part where it asks me for the input file? It would be really helpful. Thank you.