Hi,
Glad to try the libredwg lib and thank you so much for your work.
I hava tried some dwg files and it works fine. But when I use this dwg file I attached with only two LINE entites, I got some wrong data. The layer object of LINE entity is null, and also the start and end point of Line entities in this dwg file is not correct, very very strange coordinates values,like [ -3.77695079567220847e+165, -2.9177506778545462e+168, 0.0 ], [ 0.0, -2.86035487996884257e+168, 0.0 ] . Code below:

Dwg_Object *ms = dwg_model_space_object (&dwg);
obj = get_first_owned_entity (ms);
while (obj)
{
if(obj->type == DWG_TYPE_LINE)
{
Dwg_Object_LAYER * dwgLayerobj =dwg_get_entity_layer(obj->tio.entity);
Dwg_Entity_LINE *line = obj->tio.entity->tio.LINE;
}
}
The dwgLayerobj is null ,and the line entity also get wrong start or end coordinate.
Could you help to check if this issue can be solved? I can open it correctly in AutoCAD or Microstation, so I think the file is ok. But I have tried other dwg files by the lib, I can get the correct values of LINE entities.
Thank you~~
d12007.zip