It has an interesting root, it comes from the Proto Indo-European word for "four", because he must watch any enclosure of four walls. This ancient word is the source of the Latin "quartus" which comes into English as "quarter"

The PIE sense is echoed a little in phrases like "living quarters", "give no quarters" etc

Only since seeing it used in 'zigs --watch' impl on Linux[1] (and the fact that I need to enable admin capabilities to run this in a container) has informed me of it's existence.

0. https://docs.kernel.org/admin-guide/filesystem-monitoring.ht...

1. https://ziggit.dev/t/initial-implementation-of-zig-build-wat...

Linux still doesn't have a networked file watching protocol, does it? Like SGI fam, which gamin is based on. I understand SMB/CIFS supports this in the protocol, but Linux clients don't, and I don't remember if Samba does as a server.

inotify is still an ugly and error-prone interface but it does basically work.

What does the situation look like on other free OSes?

A common related requirement is to access a given version of a file, for example so that you know it's consistent with itself. Linux does support so-called "reflinks" for this... but ext4 doesn't. Sad trombone.

I guessed the date(s) indicated the tool's approximate period of active development, but apparently not ? Eg watchexec says "2016-2019" but had a major release a few days ago.

[Ah. Because this post is from 2019, and wasn't flagged as such on HN, and the list needs updating.]