rename detection without timeout

[benmccann]

It seems the current implementation depends on a timeout. Is it possible to avoid this at least in some cases such as when the native watcher is used?

• inotify has IN_MOVED_FROM and IN_MOVED_TO
• Node's native fs.watch has an eventType which is either 'change' or 'rename'. It fires for both the old location and new location. Though it seems this is how the underlying inotify API works
• Perhaps using inode number together with birthtime? (Add a file "rename" event paulmillr/chokidar#303 (comment))

[benmccann]

I think it's basically impossible. inotify just doesn't support it

• https://stackoverflow.com/questions/16204646/does-inotify-group-in-moved-from-and-in-moved-to
• https://stackoverflow.com/questions/20300955/detecting-foreign-in-moved-from-renames-with-inotify

I'm less clear on whether fanotify might support it, but the fanotify API looks quite similar to the inotify API, so I don't necessarily expect a different result there

[benmccann]

Actually, I think you can do this using fanotify:

The event FAN_RENAME may contain two information records. One of type FAN_EVENT_INFO_TYPE_OLD_DFID_NAME identifying the old directory entry, and another of type FAN_EVENT_INFO_TYPE_NEW_DFID_NAME identifying the new directory entry.

[benmccann]

A couple issues with fanotify:

• you'd need a native implementation to use it unless Node.js implements support for it
• it can be tricky to use together with docker (Use fanotify on Linux? parcel-bundler/watcher#87 (comment))

[fabiospampinato]

Yeah I think this is impossible right now given that a goal of the project is to have zero native dependencies like that (unlike stuff like chokidar).

It would be ideal though, happy to reopen if it ever becomes possible.