I have equipped my vdr system with a solid-state relay that can power on and off the monitor and speakers. The relay should be connected to the value of Setup.Suspend (see my patch from yesterday).
I am not too familiar with the plugin interface of vdr, but I got the impression that the only way to implement such a relay control in a plugin would be by polling, which is inefficient.
Are there any plans to allow plugins to register for updates of cSetup variables? (Or any plans for a svdrp interface to setting and querying the variables, for that matter?)
Such an event interface could also be to a popen'ed child process. Whenever something of interest happens, vdr would write a line to the pipe. At the very least, changes to setup variables (both vdr and plugins) would be logged. The child process would look for interesting lines, such as "Setup.Suspend=0" or "Setup.Suspend=1" in the case of relay control. Other events that could be logged would be changes in aspect ratio and play mode.
Making the event interface to a child process would avoid licensing problems. Before I decided to build a solid-state relay box myself, I searched for existing solutions. I found a manufacturer of USB-controlled power outlets that appeared to supply Linux drivers. Unfortunately, the driver turned out to be a closed-source library, which couldn't be used in a vdr plugin without breaking the GPL.
Marko