Is it possible to load a tensorflow model per file not per directory [C/C++]

It is for our project mandotary, that the network is loaded by file not per directory.

At the moment I load per directory the saved_model.pb this way and it is working:

   auto tfSessionOpts = TF_NewSessionOptions();
   runOpts = nullptr:
   TF_Session * pSession = TF_LoadSessionFromSavedModel(tfSessionOpts,

Now I have to switch to a load per file methode, while using the c_apiI have a frozen_graph.pb which I want to load in C and get some information from it.

What I do is:

Load the frozen_graph.pb into the buffer:

    std::ifstream f(m_strModelFile, std::ios::binary);
    if (f.seekg(0, std::ios::end).fail()) { throw; }
    auto fsize = f.tellg();
    if (f.seekg(0, std::ios::beg).fail()) { throw; }
    if (fsize <= 0) { throw; }
    auto data = static_cast<char*>(std::malloc(fsize));
    if (, fsize).fail()) { throw; }
    TF_Buffer* pBuffer = TF_NewBuffer();
    pBuffer->data = data;
    pBuffer->length = fsize;
    pBuffer->data_deallocator = DeallocateBuffer;

load the graph with the buffer (status is okay):

    TF_ImportGraphDefOptions* pGraphDefOptions = TF_NewImportGraphDefOptions();
    TF_GraphImportGraphDef(m_graph, pBuffer, pGraphDefOptions, status);

load the session (status is okay):

    auto tfSessionOpts = TF_NewSessionOptions();
    TF_Session* session = TF_NewSession(m_graph, sessionOptions, status);

Well, the buffer has the correct size, the graph and session is not nullptr and status says “ok”.
But when I want to use the graph, then there is no information I can use.
Like for example I can not get specific Operation:

    auto input_op = TF_Output{ TF_GraphOperationByName(m_graph, "StatefulPartitionedCall"), 1 };
    if (input_op.oper == nullptr)
     throw; // this happens

But this is possible, when I construct the graph with the TF_LoadSessionFromSavedModel function.

Am I doing sth. wrong or can a graph with usefull information not be loaded per filename?

If it is not possible with the c_api, is it possible with the c++ API?