gistfile1.c

    unsigned char* bin_data;
    bin_data = enif_make_new_binary(env, buflen, ret);

    i = 0;
    bin_data[i] = ctx->size;
    i += sizeof(length_t);
    bin_data[i] = ctx->begin;
    i += sizeof(length_t);
    bin_data[i] = ctx->filled;
    i += sizeof(unsigned short int);
    bin_data[i] = ctx->type;