How to read xgboost binary buffer file

It will be very convenient that one can read xgboost binary buffer file from someone else, explore sample data. But how to open and read it?

Are you referring to the model file? You can save it using the JSON format for easy inspection

I mean the binary buffer file that used to construct xgboost.DMatrix

There isn’t currently a way to read the binary buffer file for DMatrix. You should use the original data source that you used to build DMatrix buffer.