How to create big test files in OS X and Linux

If you need to have large files to test your application, there is a command in OS X and Linux that allows you to create a file of an arbitrary size.

We already know that you can create an empty file by using touch:

touch myfile.ext

You can also create files with a preset size with the mkfile command:

mkfile -n 2g my2gbfile.ext

That's it! You now have a 2 gigabyte file called my2gbfile.ext in your directory.