fswatch provides simple UNIX file system watching in Go. It is based around the Watcher struct, which should be initialised with either NewWatcher or NewAutoWatcher. Both functions accept a variable number of string arguments specfying the paths to be loaded, which may be globbed, and return a pointer to a Watcher. This value can be started and stopped with the Start() and Stop() methods. The Watcher will automatically stop if all the files it is watching have been deleted.

The Start() method returns a read-only channel that receives Notification values. The Stop() method closes the channel, and no files will be watched from that point.

The list of files being watched may be retrieved with the Watch() method and the current state of the files being watched may be retrieved with the State() method. See the go docs for more information.

In synchronous mode (i.e. Watchers obtained from NewWatcher()), deleted files will not be removed from the watch list, allowing the user to watch for files that might be created at a future time, or to allow notification of files that are deleted and then recreated. The auto-watching mode (i.e. from NewAutoWatcher()) will remove deleted files from the watch list, as it automatically adds new files to the watch list.

There are two types of Watchers:

• static watchers watch a limited set of files; they do not purge deleted files from the watch list.
• auto watchers watch a set of files and directories; directories are watched for new files. New files are automatically added, and deleted files are removed from the watch list.

Take a look at the provided clinotify/clinotify.go for an example; the package is also well-documented. See the godocs for more specifics.

fswatch is licensed under the ISC license.