This is supposed to create a file in my project directory called \"tuna.txt\". When I run it, it compiles successfully, however no file is created. I am on a mac using xcode
In the Products folder (in the Project Navigator of the Navigator tab on the left-hand side of the Xcode IDE) you will find the executable. Click on the executable.
If not already shown, make sure the Utilities tab on the right hand-side of the Xcode IDE is shown and the Show the file inspector is selected.
From the inspector, you will see Full Path showing the path to the executable, and at the end of it, there will be an arrow. Clicking on this arrow will open up the Finder window to that location, and this is where you should also see all the text files and other files that have been created from within the program.
PS. The reason that you couldn't find the tuna.txt file when using the search is because it is in a hidden folder along with the executable.