Path: csiph.com!usenet.pasdenom.info!weretis.net!feeder1.news.weretis.net!feeder.erje.net!1.eu.feeder.erje.net!newsfeed.xs4all.nl!newsfeed7.news.xs4all.nl!post.news.xs4all.nl!not-for-mail Return-Path: X-Original-To: python-list@python.org Delivered-To: python-list@mail.python.org X-Spam-Status: OK 0.001 X-Spam-Evidence: '*H*': 1.00; '*S*': 0.00; 'cache': 0.05; 'from:addr:yahoo.co.uk': 0.05; 'importerror:': 0.05; 'memory.': 0.05; 'python3': 0.05; 'sys': 0.05; 'exist,': 0.07; 'shutil': 0.07; 'subject:code': 0.07; '"w")': 0.09; 'foo,': 0.09; 'received:80.91': 0.09; 'received:80.91.229': 0.09; 'received:gmane.org': 0.09; 'received:list': 0.09; 'python': 0.10; 'ignore': 0.14; 'subject: \n ': 0.15; 'ignores': 0.16; 'received:80.91.229.3': 0.16; 'received:plane.gmane.org': 0.16; 'subject:import': 0.16; 'wrote:': 0.16; 'try:': 0.18; 'thanks.': 0.18; 'language': 0.19; 'lawrence': 0.22; 'second': 0.24; 'import': 0.24; 'header:In-Reply-To:1': 0.24; 'header:User- Agent:1': 0.26; "doesn't": 0.26; 'header:X-Complaints-To:1': 0.26; 'skip:# 10': 0.27; 'looks': 0.29; 'subject:that': 0.29; 'code:': 0.29; 'there.': 0.30; 'language.': 0.32; 'source': 0.33; 'url:python': 0.33; 'foo': 0.33; 'except': 0.34; 'fail': 0.35; 'url:org': 0.36; 'to:addr:python-list': 0.36; 'subject:?': 0.36; 'subject:: ': 0.37; 'received:org': 0.37; 'doing': 0.38; 'skip:o 20': 0.38; 'hi,': 0.38; 'subject:the': 0.39; 'to:addr:python.org': 0.40; 'mark': 0.40; 'body': 0.61; 'side': 0.62; 'here:': 0.63; 'our': 0.64; 'url:me': 0.64; 'here': 0.66; '8bit%:100': 0.70; 'url:c': 0.76; 'location?': 0.84; 'pythonistas,': 0.84; 'skip:\xe5 40': 0.84; 'subject:Where': 0.84; 'subject:source': 0.84; 'url:cpython': 0.84; 'url:show': 0.84; 'forever.': 0.93 X-Injected-Via-Gmane: http://gmane.org/ To: python-list@python.org From: Mark Lawrence Subject: Re: Where is the c source code of the import mechanism that ignores invalid directory? Date: Tue, 21 Jul 2015 17:16:27 +0100 References: Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Gmane-NNTP-Posting-Host: host-78-147-188-8.as13285.net User-Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.1.0 In-Reply-To: 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: , Newsgroups: comp.lang.python Message-ID: Lines: 52 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1437495414 news.xs4all.nl 2897 [2001:888:2000:d::a6]:43394 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:94297 On 21/07/2015 16:35, Shiyao Ma wrote: > Hi, > > It looks to me that the import system of Python will ignore invalid > directories and cache the result in memory. > > For example, the following code: > paste here: https://bpaste.net/show/b144deb42620 > > #!/usr/bin/env python3 > > import sys > import os > import shutil > > sys.path.append("./test") > shutil.rmtree("./test", ignore_errors=True) > > try: > import foo > except ImportError: > os.mkdir("./test") > with open("./test/foo.py", "w") as f: > f.write("print(3)") > > import foo > > the second import foo will fail even though it's there. This is because > when doing the first import foo, the directory .test doesn't exist, and > Python ignores that directory forever. > > > I am interested in the c side implementation of this "ignoring" part. > > > Any body help me to pinpoint the exact c source location? > > Thanks. > > -- > > 吾輩は猫である。ホームーページはhttps://introo.me 。 > Start here https://hg.python.org/cpython/file/6629773fef63/Python/import.c -- My fellow Pythonistas, ask not what our language can do for you, ask what you can do for our language. Mark Lawrence