Teena aims to be a collection of ports of UNIX and Linux syscalls to pure Python, with an emphasis on performance and correctness. Windows support is not a primary concern—I’m initially targeting only POSIX-compliant operating systems. The library uses Tornado to do efficient asynchronous I/O.

The first version of this library will contain implementations of tee and splice which operate on files, sockets, and file descriptors. There’s also a Capture class which behaves like StringIO, but it has a fileno() and so can be used where a real file descriptor is needed.

I’ll demonstrate how to capture the result of an HTTP request, whilst efficiently streaming the response to stderr.

Do the necessary imports:

>>> from contextlib import closing
>>> import teena
>>> import os
>>> import sys
>>> import urllib2

Create a teena.Capture() object to capture the output:

>>> capture = teena.Capture()

Open a connection using urllib2.urlopen(). This connection object has an associated file descriptor, so you can pass it directly into tee():

>>> with closing(urllib2.urlopen('http://whatthecommit.com/index.txt')) as conn:
...     teena.tee(conn, (sys.stderr, capture.input))
This really should not take 19 minutes to build.
>>> print repr(capture.getvalue())
'This really should not take 19 minutes to build.\n'

pip install teena

Copyright (C) 2012 Zachary Voase

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.