I know I can use
quota to limit the amount of disk space per user. However I'm wondering if there's some way in Linux to limit the disk usage of a directory? Ideally I'd like something like
limit_space -n 100M ./path/to/directory
And any attempts to create a file or write to a file that would make it more than 100MB would fail with a similar error as if you tried to write to a full disk.
I know it gets complicated because of symlinks and hardlinks and block sizes and stuff.
The reason I'm asking is that I have a programme that downloads files to a temporary directory, and I want to test that that it does the right thing if it can't write the file. Simulating a full disk would be one of the ways. If there's a quick one-liner like this, then I can test this easily.