Mailman 3 July 2009 - Python-Dev

Py_TPFLAGS_HEAPTYPE too overloaded
by Joshua Haberman 30 Jul '09

30 Jul '09

I'm writing a C Python extension that needs to generate PyTypeObjects dynamically. Unfortunately, the Py_TPFLAGS_HEAPTYPE flag is overloaded in a way that makes it difficult to achieve this goal. The documentation for Pt_TPFLAGS_HEAPTYPE says: Py_TPFLAGS_HEAPTYPE This bit is set when the type object itself is allocated on the heap. In this case, the ob_type field of its instances is considered a reference to the type, and the type object is INCREF’ed when a new instance is created, and DECREF’ed when an instance is destroyed (this does not apply to instances of subtypes; only the type referenced by the instance’s ob_type gets INCREF’ed or DECREF’ed). This sounds like exactly what I want. I want my type object INCREF'd and DECREF'd by its instances so it doesn't leak or get deleted prematurely. If this were all that Py_TPFLAGS_HEAPTYPE did, it would work great for me. Unfortunately, Py_TPFLAGS_HEAPTYPE is also overloaded to mean "user-defined type" (as opposed to a built-in type). It controls numerous subtle behaviors such as: - whether the type's name is module.type or just type. - whether you're allowed to set __name__, __module__, or __bases__ on the type. - whether you're allowed to set __class__ on instances of this type. - whether the module name comes from the type name or the __module__ attribute. - whether it will use type->tp_doc as the docstring - whether its repr() calls it a "class" or a "type". - whether you can set attributes of the type. - whether someone is attempting the Carlo Verre hack. So I'm stuck with an unenviable choice. I think the lesser of two evils is to *not* specify Py_TPFLAGS_HEAPTYPE, because the worst that will happen is that my types will leak. This is not as bad as having someone set __class__ on one of my instances, or set attributes on my type, etc. Ideally the interpreter would have a separate flag like Py_TPFLAGS_BUILTIN that would trigger all of the above behaviors, but still make it possible to have dynamically generated built-in types get garbage collected appropriately. At the very least, the documentation I cited above should make it clear that Py_TPFLAGS_HEAPTYPE controls more than just whether the type gets INCREF'd and DECREF'd. Based on the list of behaviors I discovered above, it is almost certainly not correct for a C exension type to be declared with Py_TPFLAGS_HEAPTYPE. Josh

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Implementing File Modes
by Eric Pruitt 30 Jul '09

30 Jul '09

Hello, Since there was a bit of confusion last time, I'll start by saying I am working on the subprocess.Popen module for Google Summer of Code. One of the features I am implementing is a class so that a running process can stand in in place of a file. For examples, instead of open( "filelist", mode = 'r') one would call ProcessIOWrapper( "ls -l", mode = 'r'). I am trying to decide if I should fully implement the mode argument. Right now, it essentially ignores everything but a 'U' indicated universal newlines in the mode argument. Should I leave that as is or make it so that things like "r+", "w", "a" are handled the way they would be for an actual file? Eric

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Update to Python Documentation Website Request
by David Lyon 29 Jul '09

29 Jul '09

Hi Greg, I'm on the python-dev mailing list and somebody gave me a link to a page that you have done: http://docs.python.org/install/ Can I ask that you also provide a link for windows users to my project: http://sourceforge.net/projects/pythonpkgmgr/ Our project provides an alternative to command line installation. And can save a lot of time for users when they wish to install packages. Thanks David

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License for code extracted from a Python library?
by Rocky Bernstein 28 Jul '09

28 Jul '09

Hi - I'm not sure if this is the right place to ask this, but I don't know of a more appropriate place. Sometime around 2007 I first extracted a function that was in Python's Cmd class and used that. Since then, I have modified and generalized it a bit more and turned it into a Python egg called columnize<http://pypi.python.org/pypi/columnize>. I also ported it to Ruby and made Ruby package or gem. A couple of people/companies have asked about redistributing this and have asked for a more MIT-like and less GPL-like license. I guess they will bundle this with their proprietary code. For the Python package, I used PSL Version 2, but is this legitimate? code.google.com doesn't seem to recognize in their list of licenses so that suggests what I did might not be the right thing. (So instead, code.google.com I selected the MIT License.) Can a MIT License be used for code extracted from Python's standard library? Other comments or suggestions? Thanks.

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Going nomail
by Aahz 28 Jul '09

28 Jul '09

I just started a new job today, and I've got a bunch of other stuff going on in my life, so I'm setting python-dev and python-ideas to nomail for a while. Please feel free to ping me directly if you want. I'll be back. -- Aahz (aahz(a)pythoncraft.com) <*> http://www.pythoncraft.com/ "Many customs in this life persist because they ease friction and promote productivity as a result of universal agreement, and whether they are precisely the optimal choices is much less important." --Henry Spencer

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mingw32 and gc-header weirdness
by Christian Tismer 27 Jul '09

27 Jul '09

Hi all, I was hacking to get mingw32 builds of psyco to work and found a pretty weird thing: I used mingw32 (stable distro) to build the psyco extension on top of standard python2.6, built with Visual Studio, and got weird crashes. The reason is in objimpl.h: typedef union _gc_head { struct { union _gc_head *gc_next; union _gc_head *gc_prev; Py_ssize_t gc_refs; } gc; long double dummy; /* force worst-case alignment */ } PyGC_Head; Mingw32 behaves funny here. The size of long double is 12 ! 8-) I happened to use the _PyObject_GC_UNTRACK macro in psyco, instead of the function, and that caused the errors, because psython and the extension disagreed on the location of the gc pointers... Using PyObject_GC_Untrack instead fixed the problem, but there is a bad feeling left. Question: Is that considered a mingw bug? Should we change the above union to a safer construct? Or maybe I just missed something obvious and made a fool out of me? cheers - chris -- Christian Tismer :^) <mailto:tismer@stackless.com> tismerysoft GmbH : Have a break! Take a ride on Python's Johannes-Niemeyer-Weg 9A : *Starship* http://starship.python.net/ 14109 Berlin : PGP key -> http://wwwkeys.pgp.net/ work +49 30 802 86 56 mobile +49 173 24 18 776 fax +49 30 80 90 57 05 PGP 0x57F3BF04 9064 F4E1 D754 C2FF 1619 305B C09C 5A3B 57F3 BF04 whom do you want to sponsor today? http://www.stackless.com/

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Backporting HTTPS via Proxy Support in urllib2
by Senthil Kumaran 25 Jul '09

25 Jul '09

Issue: http://bugs.python.org/issue1424152 mentions about HTTPS Support via proxy in urllib2. This is fixed in the trunk (Revision 72880), but there has been number of valid requests to backport it Python 2.6. While I agree and ready to backport to Python 2.6, I would like to ask here if there are any objections in this front. I am ready with the Python 3.x patch as well (with tests passed and tested under proxy setup). I shall apply that too, which is pending for a while now. :( -- Senthil Wad some power the giftie gie us To see oursels as others see us. -- R. Burns

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command line attachable debugger
by Edward Peschko 25 Jul '09

25 Jul '09

all, I'I was wondering if there was a command line python debugger that was able to attach to an existing process. I'd very much like to be able to debug over a ssh session using screen. Ed (ps - and yes, I know about winpdb, etc... that is not exactly what I'm looking for..)

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Document None values in sys.modules?
by Georg Brandl 24 Jul '09

24 Jul '09

Hi all, is the presence of None values in sys.modules considered an implementation detail? If not, it should be documented what the None values mean to the interpreter. Georg -- Thus spake the Lord: Thou shalt indent with four spaces. No more, no less. Four shall be the number of spaces thou shalt indent, and the number of thy indenting shall be four. Eight shalt thou not indent, nor either indent thou two, excepting that thou then proceed to four. Tabs are right out.

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Summary of Python tracker Issues
by Python tracker 24 Jul '09

24 Jul '09

ACTIVITY SUMMARY (07/17/09 - 07/24/09) Python tracker at http://bugs.python.org/ To view or respond to any of the issues listed below, click on the issue number. Do NOT respond to this message. 2278 open (+41) / 16106 closed (+16) / 18384 total (+57) Open issues with patches: 897 Average duration of open issues: 661 days. Median duration of open issues: 413 days. Open Issues Breakdown open 2245 (+41) pending 33 ( +0) Issues Created Or Reopened (58) _______________________________ warnings.warn segfaults on bad formatted string 07/18/09 CLOSED http://bugs.python.org/issue6415 reopened r.david.murray patch lib2to3 fails to convert 'thread' when not followed by a period 07/17/09 CLOSED http://bugs.python.org/issue6506 created ericp Enhance dis.dis to autocompile codestrings 07/17/09 http://bugs.python.org/issue6507 created tjreedy expose setresuid 07/17/09 http://bugs.python.org/issue6508 created solinym re.py - <compiled byte-object regular expr> encounter unexpected 07/18/09 http://bugs.python.org/issue6509 created kaizhu zipfile: OSError File exists 07/18/09 CLOSED http://bugs.python.org/issue6510 created srid zipfile: Invalid argument when opening zero-sized files 07/18/09 http://bugs.python.org/issue6511 created srid UnicodeDecodeError: 'utf8' codec can't decode bytes in position 07/18/09 CLOSED http://bugs.python.org/issue6512 created wplappert Standard Library, Warnings, 28.5.4, example fails 07/18/09 CLOSED http://bugs.python.org/issue6513 created jasontiller "python -m unittest <testmodule>" does not run any tests 07/18/09 CLOSED http://bugs.python.org/issue6514 created exarkun http://docs.python.org/dev/library/unittest.html#load-tests-prot 07/18/09 http://bugs.python.org/issue6515 created exarkun reset owner/group to root for distutils tarballs 07/18/09 http://bugs.python.org/issue6516 created till configparser: add possibility to escape formatstrings 07/18/09 http://bugs.python.org/issue6517 created till patch Enable 'with' statement in ossaudiodev module 07/19/09 http://bugs.python.org/issue6518 created jjalocha Reorder 'with' statement for files in Python Tutorial 07/19/09 http://bugs.python.org/issue6519 created jjalocha urllib.urlopen does not have timeout parameter where as urllib2. 07/19/09 http://bugs.python.org/issue6520 created orsenthil easy Contradictory documentation for email.mime.text.MIMEText 07/19/09 http://bugs.python.org/issue6521 created pitrou docs for unittest.expectedFailure do not syntactically show it's 07/20/09 http://bugs.python.org/issue6522 created brett.cannon smtplib exception smtp.connect TypeError encode_plain 07/20/09 http://bugs.python.org/issue6523 created kmcguire tarfile module missing decompression support? 07/20/09 CLOSED http://bugs.python.org/issue6524 created hravnx Problem with string.lowercase in Windows XP 07/20/09 CLOSED http://bugs.python.org/issue6525 created PeterL importlib.import_module affects permissions of .pyc files subseq 07/20/09 http://bugs.python.org/issue6526 created r.david.murray patch test_ttk_guionly buildbot test crash: Tcl_FinalizeNotifier: noti 07/20/09 http://bugs.python.org/issue6527 created r.david.murray builtins colored as keyword at beginning of line 07/20/09 http://bugs.python.org/issue6528 created Freiddie get{pw,gr}{nam,[ug]id}() calls are not re-entrant 07/20/09 http://bugs.python.org/issue6529 created dhduvall Regression on "python -Wi" crash 07/21/09 CLOSED http://bugs.python.org/issue6530 created kbk needs review atexit_callfuncs() crashing within Py_Finalize() when using mult 07/21/09 http://bugs.python.org/issue6531 created grahamd thread.get_ident() should return unsigned value 07/21/09 http://bugs.python.org/issue6532 created sargo Make test_xmlrpc_net functional in the absence of time.xmlrpc.co 07/21/09 http://bugs.python.org/issue6533 created r.david.murray patch, patch, easy os.makedirs returns EACCES for "C:\" 07/21/09 CLOSED http://bugs.python.org/issue6534 created luke-jr optparse required field for Options 07/21/09 http://bugs.python.org/issue6535 created mindvirus patch, easy urllib2 howto contains typo 07/21/09 CLOSED http://bugs.python.org/issue6536 created kurtmckee string.split shouldn't split on non-breaking spaces 07/21/09 CLOSED http://bugs.python.org/issue6537 reopened ericp MatchObject is not a hyperlink in the 're' module documentation 07/21/09 http://bugs.python.org/issue6538 created r.david.murray easy unittest dir not created during install 07/21/09 CLOSED http://bugs.python.org/issue6539 created kbk patch, needs review bytearray.translate(): error in error handling 07/22/09 CLOSED http://bugs.python.org/issue6540 created haypo patch SpooledTemporaryFile breakages 07/22/09 http://bugs.python.org/issue6541 created leonov patch test_os TestInvalidFD.test_closerange causes test_pipes hang in 07/22/09 CLOSED http://bugs.python.org/issue6542 created r.david.murray patch traceback presented in wrong encoding 07/22/09 http://bugs.python.org/issue6543 created r_mosaic patch, needs review Fix refleak in kqueue implementation 07/22/09 http://bugs.python.org/issue6544 created georg.brandl patch test fails in distutils.tests.test_extensions if -O is used 07/22/09 CLOSED http://bugs.python.org/issue6545 created tarek [Distutils][PATCH] Add bdist_rpm option to select the name of th 07/22/09 http://bugs.python.org/issue6546 created OG7 patch shutil.copytree fails on dangling symlinks 07/22/09 http://bugs.python.org/issue6547 created TTimo cmath documentation misleading: suggests existence of real() an 07/22/09 http://bugs.python.org/issue6548 created marketdickinson patch ttk.Style not translating some Tcl options 07/22/09 http://bugs.python.org/issue6549 created markroseman asyncore incorrect failure when connection is refused and using 07/22/09 http://bugs.python.org/issue6550 created nirs patch test_codecs fails when ran after test_zipimport and test_mailbox 07/23/09 http://bugs.python.org/issue6551 created alexandre.vassalotti Build Applet.app 07/23/09 http://bugs.python.org/issue6552 created MartienF cPickle "binunicode" segmentation fault 07/23/09 CLOSED http://bugs.python.org/issue6553 created boogenhagn patch Do we have something like os.pid_exists()? 07/23/09 http://bugs.python.org/issue6554 created pmolina distutils config file should have the same name on both platform 07/23/09 http://bugs.python.org/issue6555 created zooko "HOME" is not a standard environment variable on Windows 07/23/09 http://bugs.python.org/issue6556 created zooko urllib.urlopen creates bad requests when location header of 301 07/23/09 http://bugs.python.org/issue6557 created till #ifdef linux is incorrect; should be #ifdef __linux__ (preferred 07/24/09 http://bugs.python.org/issue6558 created yaneurabeya [PATCH]add pass_fds paramter to subprocess.Popen() 07/24/09 http://bugs.python.org/issue6559 created zhigang patch socket sendmsg(), recvmsg() methods 07/24/09 http://bugs.python.org/issue6560 created synapse patch Regex '\d' should not match unicode category 'No'. 07/24/09 http://bugs.python.org/issue6561 created marketdickinson patch OverflowError in RLock.acquire() 07/24/09 http://bugs.python.org/issue6562 created davidar Issues Now Closed (37) ______________________ atexit module not safe in Python 3.0 with multiple interpreters 270 days http://bugs.python.org/issue4200 grahamd patch, needs review bugs in array.array with exports (buffer protocol) 230 days http://bugs.python.org/issue4509 alexandre.vassalotti patch, needs review urllib2.py timeouts do not propagate across redirects for 2.6.1 170 days http://bugs.python.org/issue5102 orsenthil patch, easy pydoc reports misleading failure if target module raises an Impo 156 days http://bugs.python.org/issue5230 r.david.murray patch, easy Python 2.6 makes .pyc/.pyo bytecode files executable 60 days http://bugs.python.org/issue6070 r.david.murray patch [IDLE] UnicodeDecodeError when invoking force-open-completions 50 days http://bugs.python.org/issue6144 ezio.melotti Make PyDescr_COMMON conform to standard C 52 days http://bugs.python.org/issue6151 alexandre.vassalotti patch, patch, needs review Make io.BytesIO and io.StringIO picklable. 46 days http://bugs.python.org/issue6218 alexandre.vassalotti patch, patch Better type checking for the arguments of io.StringIO 43 days http://bugs.python.org/issue6241 alexandre.vassalotti patch Fix reference leak in io.StringIO 43 days http://bugs.python.org/issue6242 alexandre.vassalotti patch Simplify string decoding in xmlrpc.client. 23 days http://bugs.python.org/issue6360 alexandre.vassalotti patch warnings.warn segfaults on bad formatted string 1 days http://bugs.python.org/issue6415 r.david.murray patch The cgi docs should advertize using "in" instead of "has_key" 17 days http://bugs.python.org/issue6423 ezio.melotti patch Fraction fails equality test with a user-defined type 11 days http://bugs.python.org/issue6431 marketdickinson patch Improve/update python.org/dev/ 8 days http://bugs.python.org/issue6449 r.david.murray easy Documentation of ElementTree.Element.getiterator implies element 3 days http://bugs.python.org/issue6489 georg.brandl 2to3 generates "from urllib.parse import pathname2url" 1 days http://bugs.python.org/issue6496 benjamin.peterson patch documentation error: missing comma between kwonlyargcount & nloc 1 days http://bugs.python.org/issue6502 georg.brandl Minor typos in tutorial (i/o chapter) 1 days http://bugs.python.org/issue6505 georg.brandl lib2to3 fails to convert 'thread' when not followed by a period 0 days http://bugs.python.org/issue6506 benjamin.peterson zipfile: OSError File exists 3 days http://bugs.python.org/issue6510 amaury.forgeotdarc UnicodeDecodeError: 'utf8' codec can't decode bytes in position 0 days http://bugs.python.org/issue6512 ezio.melotti Standard Library, Warnings, 28.5.4, example fails 0 days http://bugs.python.org/issue6513 georg.brandl "python -m unittest <testmodule>" does not run any tests 2 days http://bugs.python.org/issue6514 michael.foord tarfile module missing decompression support? 0 days http://bugs.python.org/issue6524 hravnx Problem with string.lowercase in Windows XP 3 days http://bugs.python.org/issue6525 PeterL Regression on "python -Wi" crash 0 days http://bugs.python.org/issue6530 benjamin.peterson needs review os.makedirs returns EACCES for "C:\" 0 days http://bugs.python.org/issue6534 amaury.forgeotdarc urllib2 howto contains typo 0 days http://bugs.python.org/issue6536 ezio.melotti string.split shouldn't split on non-breaking spaces 0 days http://bugs.python.org/issue6537 benjamin.peterson unittest dir not created during install 0 days http://bugs.python.org/issue6539 benjamin.peterson patch, needs review bytearray.translate(): error in error handling 0 days http://bugs.python.org/issue6540 georg.brandl patch test_os TestInvalidFD.test_closerange causes test_pipes hang in 1 days http://bugs.python.org/issue6542 r.david.murray patch test fails in distutils.tests.test_extensions if -O is used 0 days http://bugs.python.org/issue6545 tarek cPickle "binunicode" segmentation fault 0 days http://bugs.python.org/issue6553 amaury.forgeotdarc patch Hang using files named prn.txt, etc 2810 days http://bugs.python.org/issue481171 amaury.forgeotdarc copy 2 725 days http://bugs.python.org/issue1764044 amaury.forgeotdarc Top Issues Most Discussed (10) ______________________________ 12 Can't import xmlrpclib, DocXMLRPCServer and SimpleXMLRPCServer 8 days open http://bugs.python.org/issue6499 10 Problem with string.lowercase in Windows XP 3 days closed http://bugs.python.org/issue6525 7 Do we have something like os.pid_exists()? 1 days open http://bugs.python.org/issue6554 7 UnicodeDecodeError: 'utf8' codec can't decode bytes in position 0 days closed http://bugs.python.org/issue6512 6 test_os TestInvalidFD.test_closerange causes test_pipes hang in 1 days closed http://bugs.python.org/issue6542 5 importlib.import_module affects permissions of .pyc files subse 4 days open http://bugs.python.org/issue6526 5 xml.sax.saxutils.XMLGenerator should write to io.RawIOBase. 186 days open http://bugs.python.org/issue4997 4 cmath documentation misleading: suggests existence of real() a 2 days open http://bugs.python.org/issue6548 4 optparse required field for Options 3 days open http://bugs.python.org/issue6535 4 configparser: add possibility to escape formatstrings 6 days open http://bugs.python.org/issue6517

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