watch

watch

watch - watch for events

Watch provides a command-line interface to the kqueue facility in BSD. Currently it allows files and processes to be watched. It has the same limitations as kqueue, however, and can only safely watch files on local UFS filesystems.

FEATURES

Can specify events interested in.
Can exit on occurence of event, or can continously watch, printing out messages for each event.
Can monitor for file creation, and across deletion and creation.
Freeware.

DEFICIENCIES

Watch uses strtonum() which at the moment is OpenBSD specific.
Be nice to do more than just files and processes.
Does not track children.

DOWNLOAD

watch is available as:

SOME EXAMPLES

To watch a file for any change:

           watch -f /etc/master.passwd

To watch a file for a write:

           watch -f /var/log/sulog -e write

To continously watch a process for forking:

           watch -ct -p `cat /var/run/sshd.pid` -e fork

To watch a daemon for exit, and log exit to syslog:

           watch -d -S daemon.err -p `cat /var/run/sshd.pid` -e exit

To take action when a process exits:

           watch -q -p `cat /var/run/inetd.pid` -e exit && /usr/sbin/inetd