> And you're talking about premature optimization. Why premature? And why should a basic library be deciding if they are premature or not? I am using Linux onl

> And you're talking about premature optimization. Why premature? And why should a basic library be deciding if they are premature or not? I am using Linux only (and most startups do that too). > We're barely out the gate with 1.0 and you're optimization how a file is touched. Sorry, who are "we"? I am discussing using .Net in context of all startups, not some particular one. What if my product is entirely about sending files? Or anything else where some Linux specific feature can make a big difference in performance, convenience or ability to share code with other people who are also using Linux only? > An optimization that would benefit very few people in the real world. It was added to operating system. That means pressure to do so had to be pretty high. And nearly all web framework on Linux are able to use it, so its no so uncommon as you may think. > If you're worrying about perf when you're streaming a file out of Ruby or Python to a browser then you need to rethink what you're trying to solve. Its not uncommon to stream files Python or Ruby never touched, just decided they should be sent. Its a perfect fit for this case, and performance of interpreted languages is not an issue here. >It doesn't change the fact that right now, you can write a asp.net core web application on windows and run it on linux. For free. Yes, you can. But you can not make full use of it. Which for me means that it makes no sense to use it there, when its competitors have no such issue.