- running on Linux
- free of charge
- formatting text
- keeping multiple notes
- hierarchical structure
- links between notes
- notes can have images and hyperlinks
- online and offline backup for all notes
- syncing between machines
- distributed, offline editing
- show some notice or warning when a note/image is deleted and there is a link to that
- show dead links
- work when no Internet connection
OneNote is a good application but it has some disadvantages. For example, a notebook could not be stored offline and online also it may contain dead links. It is also not free and it only works on Windows, although it is available on the web - I'm looking for both offline and online editing. What could be a good replacement given those requirements?
It is not necessary to be available "from outside" (e.g. a web service), and a local app suffice. No specific wiki format is preferred. Also, I prefer an open source software (for more security).