On Thu, Oct 12, 2006 at 12:38:51AM -0600, Travis Oliphant wrote: > > I made some fixes to the "asbuffer" code which let me feel better about > exposing it in NumPy (where it is now named int_asbuffer). > > This code takes a Python integer and a size and returns a buffer object > that points to that memory. A little test is performed by trying to > read (and possibly write if a writeable buffer is requested) to the > first and last elements of the buffer. Any segfault is trapped and used > to raise a Python error indicating you can't use that area of memory. > > It doesn't guarantee you won't shoot yourself, but it does make it more > difficult to segfault Python. Previously a simple int_asbuffer(3423423, > 5) would have segfaulted (unless by chance you the memory area 3423423 > happens to be owned by Python).
Some argument checking and a docstring would be helpful. I guessed wrong the first time: In [1]: x = N.array([1,2,3]) In [4]: y = N.int_asbuffer(x.size,x.__array_interface__['data'][0]) In [5]: y[0] Segmentation fault Out of curiosity, why does the following outputs differ: In [39]: y = N.int_asbuffer(0L,x.size) --------------------------------------------------------------------------- exceptions.SystemError Traceback (most recent call last) /home/stefan/<ipython console> SystemError: error return without exception set In [40]: y = N.int_asbuffer(1L,x.size) --------------------------------------------------------------------------- exceptions.ValueError Traceback (most recent call last) /home/stefan/<ipython console> ValueError: cannot use memory location as a buffer. Thanks for your work on this. Cheers Stéfan ------------------------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 _______________________________________________ Numpy-discussion mailing list Numpy-discussion@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/numpy-discussion
