Unix filesystem hook

Question

I'd like to add a hook to the file system, so I can execute a process whenever a specific file is read from disk. Does *nix provide a way to create such a hook? (I have root access)

Answer 1

incron, based on inotify, implements just such a hook in a cron-like way. Unfortunately, it is Linux-specific, not generic to UNIX.

Answer 2

If you run Solaris 10 or newer, an OpenSolaris based distribution, FreeBSD, (a recent) NetBSD or MacOS X, a dtrace script will easily do that job.