[Security-sig] Implementation of the PEP 524

[Victor Stinner]

Hi,

I wrote a first implementation of the PEP 524 (make os.urandom blocking):

* https://bugs.python.org/issue27776 : "PEP 524: Make os.urandom()
blocking on Linux"
* https://bugs.python.org/issue27778 : "PEP 524: Add os.getrandom()"

My patches are now waiting for your review :-)

You should also review changes made to prepare the issue #27776:

https://hg.python.org/cpython/rev/980e2c781810
https://hg.python.org/cpython/rev/265644bad99e
https://hg.python.org/cpython/rev/86d0d74bc2e1
https://hg.python.org/cpython/rev/ad141164c792

The last change (close fd on error) is not a really bugfix, it's more
a new feature. In Python 3.5, it wasn't needed to close the file
descriptor since Py_FatalError() was called immediatly.

Victor