Path: csiph.com!v102.xanadu-bbs.net!xanadu-bbs.net!feeder.erje.net!eu.feeder.erje.net!xlned.com!feeder3.xlned.com!newsfeed.xs4all.nl!newsfeed4.news.xs4all.nl!xs4all!newsgate.cistron.nl!newsgate.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 0.000 X-Spam-Evidence: '*H*': 1.00; '*S*': 0.00; 'subject:Python': 0.06; 'assuming': 0.09; 'deprecated': 0.09; 'framework.': 0.09; 'received:80.91': 0.09; 'received:80.91.229': 0.09; 'received:gmane.org': 0.09; 'received:list': 0.09; 'snippet': 0.09; 'runs': 0.10; 'subject:How': 0.10; 'python': 0.11; 'c/c++': 0.16; 'ctypes.': 0.16; 'itself,': 0.16; 'modules.': 0.16; 'presume': 0.16; 'rather,': 0.16; 'received:80.91.229.3': 0.16; 'received:plane.gmane.org': 0.16; 'set,': 0.16; 'supplied': 0.16; 'traceback.': 0.16; 'url:file': 0.16; 'ignore': 0.16; 'wrote:': 0.18; 'trying': 0.19; 'addition,': 0.20; '(the': 0.22; 'import': 0.22; 'load': 0.23; 'header:User-Agent:1': 0.23; 'error': 0.23; 'instead.': 0.24; 'sorry,': 0.24; 'specify': 0.24; 'looks': 0.24; 'question': 0.24; "i've": 0.25; 'header:X-Complaints-To:1': 0.27; 'tried': 0.27; 'function': 0.29; 'appear': 0.29; 'sets': 0.30; "i'm": 0.30; 'code': 0.31; 'ctypes': 0.31; 'flags': 0.31; 'probably': 0.32; 'url:python': 0.33; 'running': 0.33; 'actively': 0.33; 'framework': 0.33; 'mac': 0.33; 'older': 0.33; 'updated': 0.34; "i'd": 0.34; 'problem': 0.35; 'but': 0.35; 'there': 0.35; 'version': 0.36; 'library.': 0.36; 'set.': 0.36; 'charset:us- ascii': 0.36; 'subject:?': 0.36; 'url:org': 0.36; 'apple': 0.38; 'to:addr:python-list': 0.38; 'recent': 0.39; 'does': 0.39; 'to:addr:python.org': 0.39; 'received:org': 0.40; 'called': 0.40; 'skip:u 10': 0.60; 'enclosed': 0.60; 'email addr:gmail.com': 0.63; 'due': 0.66; 'anything.': 0.68; 'influence': 0.74; 'received:204': 0.75; 'article': 0.77; 'received:204.14': 0.84; 'url:cpython': 0.84 X-Injected-Via-Gmane: http://gmane.org/ To: python-list@python.org From: Ned Deily Subject: Re: How to disable RTLD_NOW for Python 2.7.x dlopen() in Mac OS X Mavericks? Date: Wed, 13 Nov 2013 19:44:44 -0800 References: Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Gmane-NNTP-Posting-Host: 204.14.154.233 User-Agent: MT-NewsWatcher/3.5.3b3 (Intel Mac OS X) X-BeenThere: python-list@python.org X-Mailman-Version: 2.1.15 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: 40 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1384400696 news.xs4all.nl 15916 [2001:888:2000:d::a6]:54703 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:59403 In article , tcwan99@gmail.com wrote: > I'm facing a problem with a 3rd party C/C++ Framework (dynamic library) on > Mac OS X which I'm trying to import into Python using ctypes. Unfortunately > OS X has deprecated a function which is called from the Framework and is no > longer available as of 10.8+ (Mtn. Lion, now updated to Mavericks). In > addition, there is no recent version of the 3rd party framework available and > it does not look like it's actively updated. (The 3rd party framework in > question is the Fantom framework/driver for the LEGO Mindstorms NXT/EV3). > > Existing tools using the 3rd party framework runs ok, but attempting to > access it using ctypes fails with a Symbol not Found error when Python 2.7.x > attempts to dlopen() the library. I suspect it is due to the setting of > RTLD_NOW when opening the framework. I'd like to try to specify RTLD_LAZY > instead. > > Unfortunately sys.setdlopenflags(0) does not appear to do anything. RTLD_NOW > is still set, which I presume overrides RTLD_LAZY if both flags were set. > I've tried this with both the Apple supplied python and the version from > MacPorts. > > Enclosed is a snippet of the code and the Traceback. Is there a way to force > RTLD_NOW off? I'm not very familiar with ctypes internals but it looks like sys.setdlopenflags is not intended to have an influence on ctypes; rather, it conditions the Python interpreter's use of dlopen to load shared Python modules. For ctypes itself, it looks like it unconditionally sets RTLD_NOW when calling dlopen and probably with good reason: http://hg.python.org/cpython/file/2.7/Modules/_ctypes/callproc.c#l1432 Sorry, I don't have a suggestion for you, assuming you want to just try to ignore the error, other than perhaps running an older version of OS X in a VM on 10.8. -- Ned Deily, nad@acm.org