Path: csiph.com!goblin3!goblin2!goblin.stu.neva.ru!news.unit0.net!news.panservice.it!bofh.it!news.nic.it!robomod From: Steve Langasek Newsgroups: linux.debian.maint.python Subject: Re: MBF for deprecating Python2 usage Date: Tue, 08 Aug 2017 07:30:03 +0200 Message-ID: References: X-Original-To: debian-python@lists.debian.org X-Mailbox-Line: From debian-python-request@lists.debian.org Tue Aug 8 05:20:59 2017 Old-Return-Path: X-Amavis-Spam-Status: No, score=-11.8 tagged_above=-10000 required=5.3 tests=[BAYES_00=-2, FOURLA=0.1, LDO_WHITELIST=-5, MURPHY_SCAM1=0.1, PGPSIGNATURE=-5] autolearn=ham autolearn_force=no X-Policyd-Weight: using cached result; rate: -5 Mail-Followup-To: Steve Langasek , debian-python@lists.debian.org MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="v55ng52gmzwjob6m" Content-Disposition: inline User-Agent: NeoMutt/20170113 (1.7.2) X-Mailing-List: archive/latest/15123 List-ID: List-URL: List-Archive: https://lists.debian.org/msgid-search/20170808052035.vx2j76cr2wugln3i@virgil.dodds.net Approved: robomod@news.nic.it Lines: 65 Organization: linux.* mail to news gateway Sender: robomod@news.nic.it X-Original-Date: Mon, 7 Aug 2017 22:20:35 -0700 X-Original-Message-ID: <20170808052035.vx2j76cr2wugln3i@virgil.dodds.net> X-Original-References: <9614BFBC-E260-48A6-B722-DDD41E715A20@kitterman.com> <92E6FF73-391C-45FE-A213-6AAED284629D@debian.org> <1502142757.2351.35.camel@ghic.org> <690EAE7E-8005-4723-891E-C2E30C3B35AD@debian.org> <85shh3lzp1.fsf@benfinney.id.au> <1502149701.2351.60.camel@ghic.org> <85inhyn8zk.fsf@benfinney.id.au> <854ltin6q1.fsf@benfinney.id.au> <1502161900.2351.65.camel@ghic.org> Xref: csiph.com linux.debian.maint.python:9742 --v55ng52gmzwjob6m Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Aug 07, 2017 at 08:11:40PM -0700, Diane Trout wrote: > > What I am opposing is the suggestion to install, in the near to > > medium > > term, a command of exactly the same name that has subtly similar but > > incompatible behaviour, when that behaviour *already* has a command =E2= =80=93 > > =E2=80=98python3=E2=80=99 =E2=80=93 that is widely used by those who ne= ed it. > my problem with that plan is all of the printed documentation saying to > learn python, type "python". > At the very least there needs to a usr/bin/python that prints > instructions about what you should run. FWIW I don't share Ben's concern about this being a "backwards incompatible" change (who is relying on the precise contents of the banner when running 'python' interactively?!). But I am concerned about possible implementation strategies here. exec() is a very expensive syscall, and python is a frequently used interpreter. If this were implemented as a wrapper that checked isatty(), printed a banner, and then re-execed the real python, that could have a measurable performance impact on some applications. There is a reason /usr/bin/python, /usr/bin/gcc, etc. are always symlinks to the real interpreter on Debian, not wrapper scripts - other distributions have tried to do this as a wrapper script and the result wasn't pretty. Avoiding the performance hit would require that any changes to the banner be made in the python source itself. --=20 Steve Langasek Give me a lever long enough and a Free OS Debian Developer to set it on, and I can move the world. Ubuntu Developer http://www.debian.org/ slangasek@ubuntu.com vorlon@debian.org --v55ng52gmzwjob6m Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIcBAABCgAGBQJZiUocAAoJEFaNMPMhshM9NNAQAL+e4fVgjFz8we5Zr4FzqtnL h66LRr4Bf0MYt+6oAByUvzzl4gDOkqCd0BYL7UkRnJPfTLeB8QYBmPqCti18gQqY RDINDA4m9LR1zuHFoQdhHROznIuqZg/oht6c/wr3qxc+aYTV0c1mrmw6kq5Scx8d YmEZglzhBDU8RJ1t6wXTgmXWJorW+YOMwYd/xtvfP8O480o8Lc/lC04QsW92BpkD Rk+OJ5PyORaMGS7zZT0h4ilkOHtyxh6uA1PhTBP1zqDmao61B0IYA6oIsJo6oncd IpPghOL3toRXWhwsNT1G/IBWIB9MgAWY1D78BZcejeCUOjM9GVggx2tn/5ltClfh 4o7Er2wQ41Xgj5N05cvhbSBboVyJgalGqdAMCNDnacG016Esd5r/CfcPia9uW9il SqkTXTV7qeCJqGhS03pJPX8xxGml/7lIzPJcE1R9qRk+bN0UZBJ3qkE1FIdmC2ld 0ZdMZd0axB3jqTdEj9kDV0tIzChPCfoFHmOPxnJnYQYQffqelJLUGNeN09csZRKg +Ff5uFOYM25T+NIVssq5tcj7aYshBC3TCTegRYJ60P0Ms5i9nubPqf2eEeAHmrWG ggQ/TFIk2td1yANEKKWD1I59cta+OyIq1GztRQ7AyjTdmrn+sw8x5wGALPg56YZU 4ou9CVA/DFG6AH5tdKdO =hI/s -----END PGP SIGNATURE----- --v55ng52gmzwjob6m--