The BUGS section in kqueue.2 is outdated. The FIFO limitation does not seem to exist anymore, AIO is not implemented at all in the kernel, and watching vnodes looks possible on all filesystem types that allow writing.
OK to remove the section? Index: kqueue.2 =================================================================== RCS file: src/lib/libc/sys/kqueue.2,v retrieving revision 1.39 diff -u -p -r1.39 kqueue.2 --- kqueue.2 1 Jul 2019 16:52:02 -0000 1.39 +++ kqueue.2 30 May 2020 09:30:12 -0000 @@ -565,7 +565,3 @@ The .Fn kqueue system and this manual page were written by .An Jonathan Lemon Aq Mt jle...@freebsd.org . -.Sh BUGS -It is currently not possible to watch FIFOs or AIO that reside -on anything but a UFS file system. -Watching a vnode is possible on UFS, NFS and MS-DOS file systems.
