1) I am trying to open a binary file.
2) With a pointer value, I am trying to read the value in memory set by the pointer. But the first value I get I want to start the pointer from 0 to a specified location.
3) I want to get that value in memory and be able to use it (i.e. int, double) so I can do math with it!!

4) I'm having trouble!!!! HELP!!!!!

Code:
		
	fstream data;
		
	data.open(filename, ios::in |ios::out | ios::binary);
	
	if(!data.is_open())
	{
		cout << "Error opening file. Please try again." << endl;
		exit(1);
	}


       ptr5 = user_def_beg_pix_ptr = (given_line - 1)*numsamples + (given_col - 1);
	
	ptr1 = ptr2 - 1;
	ptr2 = ptr5 - numsamples;
	ptr3 = ptr2 + 1;
	ptr4 = ptr5 - 1;
	ptr6 = ptr5 + 1;
	ptr7 = ptr8 - 1;
	ptr8 = ptr5 + numsamples;
	ptr9 = ptr8 +1;
	
	ptr5 = ptr5*sizeof(float);
	ptr6 = ptr6*sizeof(float);
	ptr4 = ptr4*sizeof(float);

//here's the important part giving me trouble 

	data.seekg(0,ios::beg);
	size = data.tellg();
	cout<< "This is the first size:" << size << endl;
			   
	value[0] = 0; //clearing first array just to test things.
	value[1] = 0;
	value[2] = 0;
	//may erase things later
	
	data.seekg(ptr1, ios::beg);
	size = data.tellg();
	cout<< "this is the second size: " << size << endl;
	
	data.write((char*) &value, sizeof value);
	data.read((char*) &value, sizeof value);
	cout << value[0] << " -next value- " << value[1]
	<< " -next value- " << value[2] << endl;
Output:




This is the first size:-1
this is the second size: -1
0 -next value- 0 -next value- 0
this is what's in ptr 96876
This is the pixel val 5: 96876
96872
96880