"Laurent Bercot" <ska-skaw...@skarnet.org> writes: >>I think it would be fair to be able to configure s6-linux-init so that >>it does not rely on specific details about what hardware is available. > > Then I have some good news for you: s6-linux-init already does not > rely on specific details about what hardware is available. > > Because if it did, and assumed that you have a virtual console, and you > didn't, then it would crash. And you would be a very sad panda. And > so would I. > > But it doesn't. > > What you're seeing is known as a run-time test: the existence of a > /dev/tty0 device is tested. And if such a device exists, then s6-l-i > attempts to support kbrequest on it. See? conditional support. It's > nice and sweet and simple and has fewer failure cases (because the > more configuration switches you have, the more you risk human error.)
No need to go sarcastic. Of-course I see that. But a run-time test does not need to spam the user-visible console with rather noisy warnings about missing features that was (on that system) never intended to be there. > When you don't have a virtual console, s6-l-i works perfectly fine. Yes, it works fine. But a warning is printed to console. And as it is so early, it is not going to the (catchall) logger, but on the physical console. > If there was no warning message, you would never have noticed the extra > system call, and you wouldn't be here asking for offline configuration > where online configuration works. But there is a warning message, and > that's what you don't like. Exactly. > So yes, the problem you have *is* the warning message per se, not the > fact that s6-l-i performs one completely undetectable superflous open() > call in headless systems. I agree. > So let's talk about the message. > I agree it's not particularly elegant to print a warning on every boot > in a normal configuration. So it could be refined: if devtmpfs can be > relied on to always provide /dev/tty0 when a console exists, then > when there's no such device, instead of "warning: missing device", > s6-l-i could print "info: headless system detected". > > I think that would be less scary than a "warning", and users of headless > and headful (?) systems could keep living together in peace and harmony. > > What do you think? That would be better. And if we could have an option for setting the verbosity level, so that info level messages could be avoided, I would be really happy ;) /Esben