- Apple OS X File System Events API.
- *BSD kqueue.
- Linux inotify.
- A stat-based backend for systems where none of the above are available.
fswatch ships with documentation in multiple formats, including man and Texinfo, but since few users have TeX installed on their systems to build the PDF manual from the Texinfo sources, and since GitHub currently offers no easy way to host a PDF file (unless you check it in with the sources), I am hosting the PDF manual my Google Drive account so that everybody can download it.