Mailman 3 April 2008 - Python-Dev

mmap documentation error (2.5.1)
by Neal Becker 25 Apr '08

25 Apr '08

mmap( fileno, length[, flags[, prot[, access]]]) (Unix version) Maps length bytes from the file specified by the file descriptor fileno, and returns a mmap object. If length is 0, the maximum length of the map will be the current size of the file when mmap() is called. flags specifies the nature of the mapping. MAP_PRIVATE creates a private copy-on-write mapping, so changes to the contents of the mmap object will be private to this process, and MAP_SHARED creates a mapping that's shared with all other processes mapping the same areas of the file. The default value is MAP_SHARED. Apparantly, this is wrong - the default is not MAP_SHARED, as I just found out the hard way.

2 2

segfault in 2.5.1
by Neal Becker 25 Apr '08

25 Apr '08

Attempt to write to a mmap which was opened mmap.PROT_READ causes python to segfault.

2 1

Proposed unittest changes
by Michael Foord 25 Apr '08

25 Apr '08

Hello all, I'm starting to put together a list of cleanups (with documentation changes) for the unittest module. I thought someone had already done this but the issue with the most comments I could find was 2578 which doesn't go into much detail: http://bugs.python.org/issue2578 The thing most people would like is test discovery - but that probably requires some discussion before anything can be added to unittest. What I would like to do is PEP-8'ify the method names (widening the API rather than shrinking it!): assert_true assert_false assert_equals assert_not_equals assert_raises set_up tear_down failure_exception (? - class attribute) TestSuite.add_test (etc) Documenting that these are to be preferred to 'assertEquals' and 'failUnlessEquals' (etc) and that the 'assert' statement should be used instead of 'assert_'. Adding the following new asserts: assert_in (member, container, msg=None) assert_not_in (member, container, msg=None) assert_is (first, second, msg=None) assert_not_is (first, second, msg=None) assert_raises_with_message (exc_class, message, callable, *args, **keywargs) A decorator to turn a test function into a TestCase ("as_test_case" ?). A simple 'RunTests' function that takes a collection of modules, test suites or test cases and runs them with TextTestRunner - passing on keyword arguments to the test runner. This makes running a test suite easier - once you have collected all your test cases together you can just pass them to this function so long as you are happy with the default runner (possibly allowing an alternative runner class to be provided as a keyword argument). I would provide an implementation for discussion of course. I would also like to make the error messages for "assert_equals" and "assert_not_equals" more useful - showing the objects that compare incorrectly even if an explicit message is passed in. Additionally, when comparing lists and tuples that are the same length show the members (and indices?) that were different. I've copied Steve Purcell into this email, but his comments on issue 2578 indicate that he is happy for 'us' to make changes and he no longer has a string sense of "ownership" of this module. Michael Foord

12 22

GSoC Student Introduction
by Nick Edds 23 Apr '08

23 Apr '08

Hello, My name is Nick Edds. I am going to be working on the 2to3 tool with Collin Winter as my mentor. More specifically, I will be working on improving the performance of the 2to3 tool in general, and its use of patterns in particular. I would like to request commit privileges to work in a sandbox branch and although I don't have any familiarity with bzr, I would be comfortable using it. Regards, Nick

8 11

Encoding detection in the standard library?
by David Wolever 23 Apr '08

23 Apr '08

Is there some sort of text encoding detection module is the standard library? And, if not, is there any reason not to add one? After some googling, I've come across this: http://mail.python.org/pipermail/python-3000/2006-September/003537.html But I can't find any changes that resulted from that thread.

17 37

pydoc works with eggs? (python-2.5.1)
by Neal Becker 23 Apr '08

23 Apr '08

pydoc blew up when I tried to view doc for pytools module, which is an egg: pydoc -p 8082 pydoc server ready at http://localhost:8082/ ---------------------------------------- Exception happened during processing of request from ('127.0.0.1', 52915) Traceback (most recent call last): File "/usr/lib64/python2.5/SocketServer.py", line 222, in handle_request self.process_request(request, client_address) File "/usr/lib64/python2.5/SocketServer.py", line 241, in process_request self.finish_request(request, client_address) File "/usr/lib64/python2.5/SocketServer.py", line 254, in finish_request self.RequestHandlerClass(request, client_address, self) File "/usr/lib64/python2.5/SocketServer.py", line 522, in __init__ self.handle() File "/usr/lib64/python2.5/BaseHTTPServer.py", line 316, in handle self.handle_one_request() File "/usr/lib64/python2.5/BaseHTTPServer.py", line 310, in handle_one_request method() File "/usr/lib64/python2.5/pydoc.py", line 1924, in do_GET self.send_document(describe(obj), html.document(obj, path)) File "/usr/lib64/python2.5/pydoc.py", line 321, in document if inspect.ismodule(object): return self.docmodule(*args) File "/usr/lib64/python2.5/pydoc.py", line 672, in docmodule contents.append(self.document(value, key, name, fdict, cdict)) File "/usr/lib64/python2.5/pydoc.py", line 322, in document if inspect.isclass(object): return self.docclass(*args) File "/usr/lib64/python2.5/pydoc.py", line 807, in docclass lambda t: t[1] == 'method') File "/usr/lib64/python2.5/pydoc.py", line 735, in spill funcs, classes, mdict, object)) File "/usr/lib64/python2.5/pydoc.py", line 323, in document if inspect.isroutine(object): return self.docroutine(*args) File "/usr/lib64/python2.5/pydoc.py", line 891, in docroutine getdoc(object), self.preformat, funcs, classes, methods) File "/usr/lib64/python2.5/pydoc.py", line 79, in getdoc result = inspect.getdoc(object) or inspect.getcomments(object) File "/usr/lib64/python2.5/inspect.py", line 521, in getcomments lines, lnum = findsource(object) File "/usr/lib64/python2.5/inspect.py", line 510, in findsource if pat.match(lines[lnum]): break IndexError: list index out of range ----------------------------------------

2 2

PyArg_ParseTuple and Py_BuildValue question
by Alvin Delagon 23 Apr '08

23 Apr '08

Hello fellow pythonistas, I'm currently writing a simple python SCTP module in C. So far it works sending and receiving strings from it. The C sctp function sctp_sendmsg() has been wrapped and my function looks like this: sendMessage(PyObject *self, PyObject *args) { const char *msg = ""; if (!PyArg_ParseTuple(args, "s", &msg)) return NULL; snprintf(buffer, 1025, msg); ret = sctp_sendmsg(connSock, (void *)buffer, (size_t)strlen(buffer), 0, 0, 0x03000000, 0, 0, 0, 0); return Py_BuildValue("b", ""); } I'm going to construct an SS7 packet in python using struct.pack(). Here's the question, how am I going to pass the packet I wrote in python to my module and back? I already asked this question in comp.lang.python but so far no responses yet. I hope anyone can point me to the right direction. Thanks in advance. --- Alvin Delagon

4 4

socket recv on win32 can be extremly delayed (python bug?)
by Robert Hölzl 23 Apr '08

23 Apr '08

hello, I tried to implement a simple python XMLRPC service on a win32 environment (client/server code inserted below). The profiler of the client told me, that a simple function call needs about 200ms (even if I run it in a loop, the time needed per call stays the same). After analysing the problem with etherreal I found out, that the XMLRPC request is transmitted via two TCP packets. One containing the HTTP header and one containting the data. But the acknowledge to the first TCP packet is delayed by 200ms. I tried around on the server side and found out that if the server reads exactly all bytes transfered in the first TCP frame (via socket.recv()), the next socket.recv(), even if reading only one byte, needs about 200 ms. But if I read one byte less than transfered in the first TCP frame and then reading 2 bytes (socket.recv(2)) there is no delay, although the same total amount of data was read. After some googling I found the website http://support.microsoft.com/?scid=kb%3Ben-us%3B823764&x=12&y=15, which proposed a workaround (modifing the registryentry for the tcp/ip driver) that did work. But modifing the clients registry settings is no option for us. Is there anybody who nows how to solve the problem? Or is it even a problem if the python socket implementation? By the way: I testet Win2000 SP4 and WinXP SP2 with Python 2.3.3 and Python 2.5.1 each. CLIENT: ---------- import xmlrpclib import profile server = xmlrpclib.ServerProxy("http://server:80") profile.run('server.test(1,2)') SERVER: ---------- import SimpleXMLRPCServer def test(a,b): return a+b server = SimpleXMLRPCServer.SimpleXMLRPCServer( ('', 80) ) server.register_function(test) server.serve_forever() -- Mit freundlichen Grüßen, Best Regards, Robert Hölzl BALTECH AG Firmensitz: Lilienthalstrasse 27, D-85399 Hallbergmoos Registergericht: Amtsgericht München, HRB 115215 Vorstand: Jürgen Rösch (Vorsitzender), Martina M. Schuster Aufsichtsratsvorsitzende: Eva Zeising

3 2

GSoC student introduction and sandbox commit privileges request
by Rodrigo Bernardo Pimentel 23 Apr '08

23 Apr '08

Hi there, I've just been accepted into this year's Google Summer of Code, to work for the Python Software Foundation on 2to3. My project is to give 2to3 fixers the ability to rank how confident they are on each fix, and let users choose to intervene manually whenever that confidence level is below a certain threshold. Among other things, this might allow fixers for situations where the code translation is not always guaranteed to be correct (like % string formatting, which came up recently in another thread). The full proposal is at http://isnomore.net/2to3 . Collin Winter will be my mentor, and I'd like to thank him and Christian Heimes for all the help they gave me in designing the project. I'd also like to thank Martin Löwis, for discussing a project with me which ended up not turning into a proposal, but helped me write the 2to3 one. Finally, I'd like to request commit privileges to work on a sandbox branch, during the Summer of Code. If you have any further questions, please feel free to contact me. I'm really looking forward to working on this project! Cheers, rbp -- Rodrigo Bernardo Pimentel <rbp(a)isnomore.net> | GPG: <0x0DB14978>

3 3

SetType=set in types module ?
by iks hefem 23 Apr '08

23 Apr '08

Hi, the SetType is not available in the "types" module, so wouldn't it be needed here ? (in 2.6 by example) I guess the change is really simple and would be backward compatible : adding SetType = set

3 2