I think a cool addition to runit program sv and s6's s6-svc would be a command to send an arbitrary signal to the daemon being supervised.
Yes, that would be a nice feature. I've been thinking about it for some time. Unfortunately, that's not at all suited to the way the control program communicates with the supervisor, and adding this feature, as simple as it seems, would require significant work. There is probably a (dirty, hackish) way to make it work with normal signals (<128). But there's absolutely no way to ever make it work with real-time signals or anything with a signal number over 128 without rewriting the supervisor state machine and making it more complex and more brittle. Which is an instant nope from me. Restricting the feature to normal signals would probably be enough, but even then, I'm not comfortable with the level of hackiness it would require. I don't think the feature is worth it; I'd rather add more signals to the explicitly supported list. -- Laurent
