Sentinel is a simple Mac OS X application which faciliates monitoring and observing command output. By allowing the process output to be monitored with periodic execution, it becomes easy to observe changes over time. In a way, Sentinel is similar to the watch command line program, but includes additional features, such as diff-ing output with previous output and colouring lines of output that have changed. The history of iterative command execution can also be examined retroactively.
Sentinel is written in Objective C and utilises Apple's Cocoa application programming interfaces. This software is distributed under the terms and conditions of the Free Software Foundation's GNU General Public License, which should accompany the application in cases of redistribution.