Filewatching fails silently with >4096 paths

[maiamcc]

Before reporting an issue, please ensure you are using the latest release of fsevents.

Which version of macOS are you using?

ProductName:	Mac OS X
ProductVersion:	10.15.4
BuildVersion:	19E287

Please describe the issue that occurred.

Filewatching with fsevents.EventStream works just fine for up to 4096 paths; from 4097 paths upwards, I don't seem to be getting any events (nor error messages).

Are you able to reproduce the issue? Please provide steps to reproduce and a code sample if possible.

Repro case here (a small Go util that watches files specified as args, plus repro instructions).

FWIW, I think this may be an underlying problem with fsevents (because I could reproduce the problem with e.g. this fswatch util), but I'm not sure where to report; would be happy for guidance!

[pbnjay]

Confirmed still an issue on 11.5.2, thanks for the repo case!
As mentioned in the linked issue, I can confirm it is associated with #37 when the FSEventStreamStart returns 0.

One workaround that is actually more performant on macOS is to simply watch the containing folder e.g. for your repro case you can use go run main.go ./files (but this does not match the expected semantics if you want a subset for 4097 files).

[nathany]

Maybe we should update the README with this limit?

[pbnjay]

I can include a README update with the changes I have queued for #37 . Trying to clean up the tests this evening