Re: [ctypes-users] allocating memory in Python and then coverting it into Physical memory

[Thomas H. <th...@ct...>]

david elsen schrieb:
> Hello all,
> 
> I am trying to use (learn) Python in Linux environment and kind of
> new to both. Know little bit about Linux, Python just started
> yesterday.
> 
> I am trying to write an application in Python which will be
> allocating memory for my header and data buffer (header is a
> structure pointer and data is an dword array pointer). Then need to
> convert this virtual memory to physical memory and pass it on to the
> IOCTL for further processing.
> 
> Some DMA operation will be performed on this passed header and data
> address.
> 
> I was suggested that I can write am application in Python by using
> CTYPES.
> 
> I no not even know how can I load the CTYPES. I tried to follow the
> documentation and did following:
> 
> #Python Python 2.4.3 (#1, Dec 11 2006, 11:38:52)
>>>>> cdll.LoadLibrary("libc.so.6")
> NameError: name 'cdll' is not defined
> 

I suggest you first start to play with Python.  Forget your concrete problem
for a while and work through the Python tutorial avaliable at www.python.org.

Then you can turn to the ctypes tutorial again and try out ctypes (although
I fear ctypes is not included in the Python 2.4 version that you have available);
you would have to install it first.  Then you wil lhave to decide whether to approach
your problem with Python, C, or whatever language.  ctypes is not really a trivial module.

Finally, a hint for your question:

You must first import the ctypes module before you can work with it; like so:

>>> from ctypes import cdll
>>> cdll.LoadLibrary("libc.so.6")

Thomas