I have latest IronPython version built and running in Ubuntu 14.04 through Mono.
Building Ironpython and running with Mono seems trivial but I am not convinced I have proper sys.paths or permissions for Ironpython to import modules, especially modules like fcntl. 
Running ensurepip runs subprocess, and wants to import "fcntl". There are numerous posts already out there, but mostly regarding windows.
As I understand, fcntl is part of unix python2.7 standard library. To start the main problem seems to be that Ironpython has no idea where this is, but I also suspect that since fcntl seems to be perl or at least not pure python, that there is more to the story.
So my related sys.path questions are:

In Ubuntu, where should I install Ironpython (Ironlanguages folder)
to? Are there any permissions I need to set?
What paths should I add to the sys.path to get Ironpython's standard library found?'
What paths should I add to the sys.path to get Ubuntu's python 2.7 installed modules?
What paths should I add to the sys.path  or methods to get fcntl to import properly in Ironpython
Any clues on how to workaround known issues installing pip through ensurepip using mono ipy.exe X:Frames ensurepip

Thanks!
As far as I can see, the fcntl module of cPython is a builtin module (implemented in C) - those modules need to be explicitly implemented for most alternative Python interpreters like IronPython (in contrast to the modules implemented in plain Python), as they cannot natively load Python C extensions.
Additionally, it seems that there currently is no such fcntl implementation in IronPython.
There is a Fcntl.cs in IronRuby, however, maybe this could be used as a base for implementing one in IronPython.
Ubuntu and Ironpython: What paths to add to sys.path AND how to import fcntl module?