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#4 Segmentation fault when reading vdata from HDF4 file
I am attempting to read a vdata field from an HDF file (version 4) using the pyhdf module.
The field is called "Lidar_Data_Altitudes" and is stored in the vdata called "metadata". So I do:
from pyhdf import VS
from pyhdf.HDF import *
hdffile = HDF(filename, HC.READ)
vs = hdffile.vstart()
vd = vs.attach('metadata', write=0)
alt = vd.field('Lidar_Data_Altitude')
the code segfaults at the last line, but any attempt to access the contents of vd (e.g. vd.read()) will segfault.
I have found a similar issue reported and resolved here: http://proj.badc.rl.ac.uk/cedaservices/ticket/37
apparently it involves a small patch to the file hdfext_wrap.c part of pyhdf.
The file I'm trying to read Lidar_Data_Altitudes from is too big to link here, but here is another HDF file from which attempting to read vdata segfaults: http://www.lmd.polytechnique.fr/~noel/Files/CAL_LID_L2_05kmCLay-Prov-V3-30.2013-08-26T14-52-35ZN.hdf
replace the last line of the sample code above with data = vd.read(), and it segfaults.
