Failure when running on ubuntu focal

[furlongm]

Stacktrace:

Traceback (most recent call last):
  File "/usr/local/bin/pcicrawler", line 8, in <module>
    sys.exit(main())
  File "/usr/local/lib/python3.8/dist-packages/click/core.py", line 1137, in __call__
    return self.main(*args, **kwargs)
  File "/usr/local/lib/python3.8/dist-packages/click/core.py", line 1062, in main
    rv = self.invoke(ctx)
  File "/usr/local/lib/python3.8/dist-packages/click/core.py", line 1404, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/usr/local/lib/python3.8/dist-packages/click/core.py", line 763, in invoke
    return __callback(*args, **kwargs)
  File "/usr/local/lib/python3.8/dist-packages/pcicrawler/cli.py", line 292, in main
    exptype = dev.express_type
  File "/usr/local/lib/python3.8/dist-packages/pci_lib/pci_lib.py", line 42, in __get__
    value = obj.__dict__[self.func.__name__] = self.func(obj)
  File "/usr/local/lib/python3.8/dist-packages/pci_lib/pci_lib.py", line 553, in express_type
    express = find_capability(config, PCI_CAP_EXPRESS)
  File "/usr/local/lib/python3.8/dist-packages/pci_lib/pci_lib.py", line 153, in find_capability
    cap_id = read_u8(config, pos)
  File "/usr/local/lib/python3.8/dist-packages/pci_lib/pci_lib.py", line 122, in read_u8
    r, = struct.unpack('B', data[offset:offset + 1])
  File "/usr/local/lib/python3.8/dist-packages/pci_lib/pci_lib.py", line 299, in __getitem__
    return b''.join(int2byte(b) for b in data)
  File "/usr/local/lib/python3.8/dist-packages/pci_lib/pci_lib.py", line 299, in <genexpr>
    return b''.join(int2byte(b) for b in data)
struct.error: required argument is not an integer```

[antgun42]

I ran into the same issue when trying to use pcicrawler in a non-privileged container, running in privileged mode solves the problem.