[ncruces]

The most egregious part of it for me is that if I open and close a file I might be canceling some other library's lock that I'm completely unaware of.

I resisted using them in my SQLite VFS, until I partially relented for WAL locks.

I wish more platforms embraced OFD locks. macOS has them, but hidden. illumos fakes them with BSD locks (which is worse, actually). The BSDs don't add them. So it's just Linux, and Windows with sane locking. In some ways Windows is actually better (supports timeouts).