Gamin is a file and directory monitoring system defined to be a subset of the
FAM (File Alteration Monitor) system. This is a service provided by a library
which allows to detect when a file or a directory has been modified.

Whereas the FreeBSD port of FAM polls files every few seconds, this port
includes a kqueue(2) backend for immediate notification of most alterations.

WWW: http://www.gnome.org/~veillard/gamin/index.html