handling buffers efficiently

i am loosing data and feel like i need some little
good tutorial on how to implement an efficient circular buffer.
If i got a buffer of size k. how to add data to it
and at the same time read data out?. I hope this
make it real time like process so that data would
not get lost. any example,..??

At the point when the buffer gets fulled with written data, you must override the first elements.

Can you explain what are you actually trying to do?

something like this?

class CircularBuffer
{
int size, front, back;
vector<int> data;

public:
CircularBuffer() : size(0), data(1), front(0), back(0) {}

CircularBuffer(int k) : size(k-1), data(k), front(0), back(0) {}

void push_back(int i) { if (++back>size) back=0; data[back]=i;}

void pop_back(int &i) { i=data[back];if (--back<0) back=size;}

void push_front(int i) { if (--front<0) front=size; data[front]=i;}

void pop_front(int &i) { i=data[front];if (++front>size) front=0;}
}

can you add main() that uses this class as a ring or circular buffer?. i created template based of a ring buffer that works ok. i have to clean it up , then i 'll post it.

two examples of circular buffer appliction that handles:
1) simultaneous read and write operations.
2) serialized read and write.
this is very important to me to understand if one has an exmples of each.

like to fit "writetobuf" and "readnextbuf" into threads for fast speed
write / read but not quite sure how.
Any changes and adds that improve things be nice.

Code:

---

int InsertNextIndex = 0;
int ReadNextIndex = 0;

#define imgIndex  20
BYTE *images[imgIndex];
bool imgIndexUsed[imgIndex];


void SetImageSize(int height, int width,
int numofbytesPerPixel = 4)
{
  imagesz = height*width*numofbytesPerPixel;
}


void BufInit(void)
{
  int i;
  for (i=0; i<imgIndex; i++)
  {
    imgIndexUsed[i] = false;
    images[i] = new BYTE[imagesz];
  }
}


bool WriteToBuf(BYTE *pdata)
{
  if (imgIndexUsed[InsertNextIndex])
    return(false);
  imgIndexUsed[InsertNextIndex] = true;

  memcpy(images[InsertNextIndex], pdata, imagesz);

  InsertNextIndex++;
  if (InsertNextIndex==imgIndex) InsertNextIndex = 0;

  return(true);
}


BYTE *ReadNextBuf(void)
{
  if (!imgIndexUsed[ReadNextIndex])
    return null;
  return(images[ReadNextIndex]);
}

void NextBufPrep(void)
{
  if (!imgIndexUsed[ReadNextIndex]) return;

  imgIndexUsed[ReadNextIndex] = false;
  ReadNextIndex++;
  if (ReadNextIndex==imgIndex) ReadNextIndex = 0;
}

void bufdestroy()
{
  int i;
  for (i=0; i<imgIndex; i++)
    delete [] images[i];
}

---