Mailman 3 December 2012 - capi-sig

Re: [capi-sig] Does Py_False or Py_True need de-referencing if used in a PyObject_Compare?
by Campbell Barton 15 Dec '12

15 Dec '12

On Fri, Dec 14, 2012 at 3:21 AM, Robert Steckroth <robertsteckroth(a)gmail.com> wrote: > Does the below statement have a memory leak? > > if ( PyObject_Compare(update_var, Py_False) > > Do I need to assign the Py_False first and DECREF it, or is the above > snippet ok alone. The python api docs will often say if they use/steal references. If your not sure you could just printf("%d\n", Py_REFCNT(Py_False)); before and after calling.

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Re: [capi-sig] Does Py_False or Py_True need de-referencing if used in a PyObject_Compare?
by Stefan Behnel 15 Dec '12

15 Dec '12

Robert Steckroth, 13.12.2012 17:57: > Well, from what I have gathered, the reference count does not need to be > maintain as far as PyBool objects go. They are like any other object, i.e. they need reference counting. > It seem to be fine even if the object is set from a argument. Hmmm... That's a different case. As long as you are sure that someone (better you) owns a reference to the object that you pass as argument, you don't need to increase its refcount just for the call. That's easy to get wrong, though. >> Does the below statement have a memory leak? >> >> if ( PyObject_Compare(update_var, Py_False) Why should it? >> Do I need to assign the Py_False first and DECREF it, or is the above >> snippet ok alone. I keep being surprised by what some people take their fun in programming from. Good to see that you're getting actual functionality done regardless. Stefan

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Re: [capi-sig] How do I get the Objects to clean up after a python script exits?
by Stefan Behnel 15 Dec '12

15 Dec '12

Robert Steckroth, 12.12.2012 19:45: > When I test my module in the interpreter it automatically cleans up any > created objects. This is a very nice feature > for my module and I would like to use it. How do I go about getting > my scripts to send an exit cleanup single? Depends on exactly what you are trying to achieve, but you might want to look at the atexit module. Py3 additionally has the PyModuleDef setup which allows you to clean up module globals at exactly the right time on interpreter tear down. It basically implements garbage collection for modules. (Shameless hint: Cython cleans up global variables for you automatically and chooses the right way to do so based on the capabilities of the current runtime.) Stefan

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Re: [capi-sig] How do I get the Objects to clean up after a python script exits?
by Stefan Behnel 15 Dec '12

15 Dec '12

Robert Steckroth, 12.12.2012 19:45: > When I test my module in the interpreter it automatically cleans up any > created objects. This is a very nice feature > for my module and I would like to use it. How do I go about getting > my scripts to send an exit cleanup single? Depends on what you are trying to achieve, but you might want to look at the atexit module. (Shameless hint: Cython cleans up global variables for you automatically.) Stefan

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Re: [capi-sig] Does Py_False or Py_True need de-referencing if used in a PyObject_Compare?
by Stefan Behnel 15 Dec '12

15 Dec '12

Robert Steckroth, 13.12.2012 17:57: > Well, from what I have gathered, the reference count does not need to be > maintain as far as PyBool objects go. They are like any other object, i.e. they need reference counting. > It seem to be fine even if the object is set from a argument. Hmmm... That's a different case. As long as you are sure that someone (better you) owns a reference to the object that you pass as argument, you don't need to increase its refcount just for the call. That's easy to get wrong, though. >> Does the below statement have a memory leak? >> >> if ( PyObject_Compare(update_var, Py_False) Why should it? >> Do I need to assign the Py_False first and DECREF it, or is the above >> snippet ok alone. I keep being surprised by what some people take their fun in programming from. Good to see that you're getting actual functionality done regardless. Stefan

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Re: [capi-sig] Does Py_False or Py_True need de-referencing if used in a PyObject_Compare?
by Robert Steckroth 13 Dec '12

13 Dec '12

Well, from what I have gathered, the reference count does not need to be maintain as far as PyBool objects go. It seem to be fine even if the object is set from a argument. Hmmm... On Thu, Dec 13, 2012 at 11:21 AM, Robert Steckroth < robertsteckroth(a)gmail.com> wrote: > Does the below statement have a memory leak? > > if ( PyObject_Compare(update_var, Py_False) > > Do I need to assign the Py_False first and DECREF it, or is the above > snippet ok alone. > > -- > Bust0ut, Surgemcgee: Systems Engineer --- > surgemcgee.com > Django_Teamplate3d > -- Bust0ut, Surgemcgee: Systems Engineer --- surgemcgee.com Django_Teamplate3d

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Does Py_False or Py_True need de-referencing if used in a PyObject_Compare?
by Robert Steckroth 13 Dec '12

13 Dec '12

Does the below statement have a memory leak? if ( PyObject_Compare(update_var, Py_False) Do I need to assign the Py_False first and DECREF it, or is the above snippet ok alone. -- Bust0ut, Surgemcgee: Systems Engineer --- surgemcgee.com Django_Teamplate3d

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How do I get the Objects to clean up after a python script exits?
by Robert Steckroth 12 Dec '12

12 Dec '12

When I test my module in the interpreter it automatically cleans up any created objects. This is a very nice feature for my module and I would like to use it. How do I go about getting my scripts to send an exit cleanup single? -- Bust0ut, Surgemcgee: Systems Engineer --- surgemcgee.com Django_Teamplate3d

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Re: [capi-sig] Open sourced the Python PySurface Module!
by Hrvoje Niksic 11 Dec '12

11 Dec '12

Robert Steckroth <robertsteckroth(a)gmail.com> writes: > Hello Gang, I have open-sourced the PySurface module and started the > documentation. I know there is some novel ideas in there for anyone in > this field, so check it out. I can't wait to slap this one into my > resume! Also, any constructive criticism is welcome as this project a > large cookie. Congratulations! However, the python mailing list/newsgroup might be a better place for the announcement, as this list has a fairly narrow audience. You might also want to put up the project on PyPI, so it gets some attention.

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Open sourced the Python PySurface Module!
by Robert Steckroth 11 Dec '12

11 Dec '12

Hello Gang, I have open-sourced the PySurface module and started the documentation. I know there is some novel ideas in there for anyone in this field, so check it out. I can't wait to slap this one into my resume! Also, any constructive criticism is welcome as this project a large cookie. I have not uploaded the Docs to ReadTheDocs.org yet, so you can scope out my in-house design and get the repository here --> www.surgemcgee.com Robert Steckroth -- Bust0ut, Surgemcgee: Systems Engineer --- surgemcgee.com Django_Teamplate3d

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