Dear GNU Prolog developers,
1.The C interface has Pl_Rd_String (it exist in code but is not documented).
2. It feels a little inconvenient in having to parse ASCII output of Pl_Rd_String back to binary in C code that consumes the Prolog output.
And it will greatly help, like other Prolog implementations, to have a interface to the Prolog internal data structures, presenting output in "in-memory binary format" of outputs.
Like an array of pointers to GNUProlog data type (struct) objects.