How to release term created by enif_make_copy

[caox]

Hi

In my experiment of erlang nif, I use an global env to store term received from erlang proc  s via enif_make_copy(). I am wondering how could I free some specific terms created on this env but not all of them? 

I didn't find any lib funcs to do this job. Both enif_clear_env() and enif_free_env() do whole cleanup, and enif_free is annotated to be used only for  memory allocated by enif_alloc.