Okay so I’m not sure if this an error with the hugo add-on, or with some setting, or something. I added a new blog post and when I went to publish it, it threw this error. I don’t have config.toml open so I’m not sure why that popped up.
Make sure your ulimit -n is high enough (16K should do it) - if you aren’t running a busy site, then it might be a bug in one of your plugins (?) that’s not closing files properly.