Path: csiph.com!fu-berlin.de!uni-berlin.de!not-for-mail From: Ben Finney Newsgroups: comp.lang.python Subject: Re: What interface is a =?utf-8?Q?=E2=80=98Popen=2Estdout?= =?utf-8?Q?=E2=80=99?= presenting? Date: Thu, 24 Dec 2015 15:40:06 +1100 Lines: 29 Message-ID: References: <85d1twzlj2.fsf@benfinney.id.au> <858u4kzkyp.fsf@benfinney.id.au> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Trace: news.uni-berlin.de yDlS+ZoKgkzlZOGsgCUNhgTzRdoNITykZvn5I2PCV8sg== Cancel-Lock: sha1:kqDWjGxwV5Ji1z2m3JmBHcx9Gog= Return-Path: X-Original-To: python-list@python.org Delivered-To: python-list@mail.python.org X-Spam-Status: OK 0.007 X-Spam-Evidence: '*H*': 0.99; '*S*': 0.00; 'wrapper': 0.07; 'descriptor': 0.09; 'mode,': 0.09; 'received:80.91': 0.09; 'received:80.91.229': 0.09; 'received:gmane.org': 0.09; 'received:list': 0.09; 'underlying': 0.09; 'python': 0.10; 'wed,': 0.15; '23,': 0.16; '8bit%:26': 0.16; 'dup': 0.16; 'received:80.91.229.3': 0.16; 'received:io': 0.16; 'received:plane.gmane.org': 0.16; 'received:psf.io': 0.16; 'stream.': 0.16; 'those,': 0.16; 'wrote:': 0.16; 'thanks.': 0.18; '2015': 0.20; 'file.': 0.22; 'dec': 0.23; 'header:User-Agent:1': 0.26; 'header:X-Complaints-To:1': 0.26; '(e.g.': 0.27; 'object,': 0.27; 'code': 0.30; 'stream': 0.33; 'wrap': 0.33; 'open': 0.33; 'file': 0.34; 'text': 0.35; 'clear': 0.35; 'functions.': 0.35; 'instance': 0.35; 'unit': 0.35; 'created': 0.36; 'to:addr:python- list': 0.36; 'subject:?': 0.36; 'pm,': 0.36; 'subject:: ': 0.37; 'received:org': 0.37; 'files': 0.38; 'test': 0.39; 'whatever': 0.39; 'to:addr:python.org': 0.40; 'close': 0.61; 'telling': 0.61; 'making': 0.62; 'believe': 0.66; 'skip:\xe2 10': 0.70; 'subjectcharset:utf-8': 0.71; '8bit%:27': 0.72; 'truth': 0.79; '_o__)': 0.84; 'mencken': 0.84; 'received:125': 0.84; '\xe2\x80\x94henry': 0.84 X-Injected-Via-Gmane: http://gmane.org/ X-Gmane-NNTP-Posting-Host: jigong.madmonks.org X-Public-Key-ID: 0xAC128405 X-Public-Key-Fingerprint: 517C F14B B2F3 98B0 CB35 4855 B8B2 4C06 AC12 8405 X-Public-Key-URL: http://www.benfinney.id.au/contact/bfinney-pubkey.asc X-Post-From: Ben Finney User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.4 (gnu/linux) X-BeenThere: python-list@python.org X-Mailman-Version: 2.1.20+ Precedence: list List-Id: General discussion list for the Python programming language List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Xref: csiph.com comp.lang.python:100793 eryk sun writes: > On Wed, Dec 23, 2015 at 7:36 PM, Ben Finney wrote: > > So how do I get from a Python 2 ‘file’ object, to whatever > > ‘io.TextIOWrapper’ wants? > > I would dup the file descriptor and close the original file. Then open > the file descriptor using io.open Thanks. Okay, now I reveal (I apologise for not making this clear initially) that I need the *same* code to work with pseudo files created by the unit test suite: files with no underlying file handle. That is, I need the same code to accept: * A Python 2 ‘file’ instance as emitted by many stdlib functions. * A Python 3 ‘io.*’ file object as emitted by many stdlib functions. * A pseudo-file (e.g. ‘io.BytesIO’) test double. With any of those, I need the code to wrap a stream already open in “binary” mode, and give me a wrapper (e.g. ‘io.TextIOWrapper’) to read and/or write text on that stream. -- \ “It is hard to believe that a man is telling the truth when you | `\ know that you would lie if you were in his place.” —Henry L. | _o__) Mencken | Ben Finney