New submission from zeero: I'm implementing a CAN SAEJ1939 stack in Python and convert CAN message ids in between integers and structures, tunneling them through a Union object with 4 bytes like what i would do in C.
I was checking that particular function and the 3 priority bits were at the wrong position. Some trials later i concluded the bits are reversed and inverted the order in my structure. Now it works fine. I'm not sure if it's a bug but i would expect ctypes.Structure to store the fields in the order i provide and not the other way around. On the other hand the bytes are in the order i provided. The System I'm running on is 64Bit Ubuntu AMD A1046 but it shows the same behaviour an a 64bit Windows 7 Intel I5 ---------- components: ctypes files: test_structure.py messages: 248536 nosy: zeero priority: normal severity: normal status: open title: ctypes.Structure bit order is reversed - counts from right type: behavior versions: Python 3.4 Added file: http://bugs.python.org/file40174/test_structure.py _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue24859> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
