I need to test my web app in a scenario where there’s no disk space remaining, i.e. I cannot write any more files. But I don’t want to fill my hard drive with junk just to make
I'm not sure of how to do it on OSX but on Linux, I'd probably put a disk quota on my test user and then run the app.
Or maybe create a null file (a small one), format it as an ext3 partition, mount it using the loopback device and run the PHP app inside it. This would be closer to a physical disk that's short of space.