This is the README for upsdeamon.N.bs.tar.gz [Download] [Browse] [Up]
The UPS monitor daemon or "upsd" watches the serial port connected to an UPS and will perform an unattended shutdown of the system if the UPS is on battery longer than a specified number of minutes. Upsd needs to watch a tty with modem control properties, and expects the UPS to raise DCD when it switches to battery backup and drop DCD when it goes back to online. Upsd was developed and tested under ISC with the FAS 2.08 driver and an American Power Conversion SmartUPS 600, your milage may vary on other OSes and UPSes.
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.