I am not able to install eventmachine
Ok I know this has been asked quite a lot, but no solutions I found has helped me so far.So I posted here as a last resort.
You can try this answer here: Rails - cannot run app: Unable to load the EventMachine C extension;
The Accepted answer to this question works. But you'll have other problems as shown in the comments below.
Follow the solution by suda in the link, you'll be fine.
(Actually, it's basically compiling and installing gem from the master github code repo. I was surprised they haven't pushed the issue fix into master yet, since they're aware of it.)