The binary files in netcdf2xdmf should not have the executable flag set: https://github.com/SeisSol/Meshing/blob/master/netcdf2xdmf/src/main.cpp#L200 See here for the correct flags: https://github.com/TUM-I5/XdmfWriter/blob/c25e98e7d3205367ad15575643af3775520367bd/backends/Posix.h#L183