C / C++ / MFC

typedef struct
{
    int updateType; // Identifies the struct member that is updated
    //int dataType;   // Optional: Data type of struct member (float, char)
    int firstNdx;   // First index for array data types
    int lastNdx;    // Optional: Last index (when multiple elements must be updated)
    int dataLen;    // Optional: Size of following data ((lastNdx - firstNdx) + 1)
                    // Multiply with size of data type for byte count 
    char data[1];   // Payload placeholder
} MyUpdateProtocol;

enum MyDataMembers
{
    IVKK,
    FIL,
    FDDD,
    FCDCP,
    // ...
};

int firstNdx = 0;
int lastNdx = 10;
int dataSize = ((lastNdx - firstNdx) + 1) * sizeof(float);
// Allocate buffer for protocol header and payload.
// Using a buffer on the stack here would be faster but
//  requires the size to be known during compilation time.
//char buf[sizeof(MyUpdateProtocol) - 1 + sizeof(float) * MAX_ELEMS_TO_BE_SEND];
char *buf = new char[dataSize + sizeof(MyUpdateProtocol) - 1];
// Cast buf to a protocol type pointer.
MyUpdateProtocol *pProto = (MyUpdateProtocol *)buf;
// Initialise the protocol header fields.
pProto->updateType = IVKK;
//pProto->dataType = MUP_FLOAT;
pProto->firstNdx = firstNdx;
pProto->lastNdx = lastNdx;
pProto->dataLen = dataSize;
// Copy the payload (pModDB is a pointer to the shared data).
memcpy(pProto->data, &pModDB->IVKK[firstNdx], dataSize);
// Send it.
// Use the real size here (subtract one byte for the data[1] member).
sendData(buf, dataSize + sizeof(MyUpdateProtocol) - 1);
delete [] buf;

// Assuming received data has been copied to char *buf
MyUpdateProtocol *pProto = (MyUpdateProtocol *)buf;
void *dest = NULL;
switch (pProto->updateType)
{
    case IVKK : dest = &pModDb->IVKK[pProto->firstNdx]; break;
    case FIL : dest = &pModDb->FIL[pProto->firstNdx]; break;
    // ...
}
memcpy(dest, pProto->data, pProto->dataLen);

enum DBENUM {
  DE_IVKK = 0,
  DE_FIL,
  DE_FDDD,
  DE_FCDCP,
  DE_FLH,
  // blah blah blah
};

BOOL DBCopyFunction (enun DBNUM whatToCopy, struct TModDB* TheDB, void* Buf, long SizeOfBuf){
   BOOL success = FALSE;    // Preset fail .. any errrors we will let drop thru
   if (TheDb){              // Check theDB ptr valid
      switch(whatToCopy){
          case DE_IVKK: {
              if (sizeof(TheDB->IVKK) <= SizeofBuf) {             // check buffer large enough
                   memcpy(Buf, TheDB->IVKK, sizeof(TheDB->IVKK)); // Copy IVK field
                   success = TRUE;                                // Field copied set success
              }
          }
          break;
          case DE_FIL: {
              if (sizeof(TheDB->FIL) <= SizeofBuf) {             // check buffer large enough
                   memcpy(Buf, TheDB->FIL, sizeof(TheDB->FIL));  // Copy FIL field
                   success = TRUE;                               // Field copied set success
              }
          }
          break;

          /// blah blah blah
      }
   }
   return (success);
} 

manoharbalu wrote:

Now I need to transfer some of the data values that are changed to another application...

int main()
{
    int s;
    int box1=3,box2=6,box3=9,box4=1,box5=s,box6=7,box7=5,box8=8,box9=2;
    
    cout << " -----------" << endl;
    cout << " | " << box1 << " | " << box2 << " | " << box3 << " | " << endl;
    cout << " -----------" << endl;
    cout << " | " << box4 << " | " << box5 << " | " << box6 << " | " << endl;
    cout << " -----------" << endl;
    cout << " | " << box7 << " | " << box8 << " | " << box9 << " | " << endl;
    cout << " -----------" << endl;
    
//       void BFS(int s);
    Graph graph = new Graph(V);  // where does the value of V come from?
    graph.addEdge(v, w);         // what are these values?
    graph.BFS(int s);            // where does the value of s come from?
    
    return 0;
}