pad print line with white space C++ - c++

Question

In C++ I am using unsigned char pointers to hold byte arrays so that I can fit 8 bit color codes in each element for a print line.
I have one array holding data, and one array holding white space, and I am using for loops to populate a third array so that the data is at the beginning and white space is at the end.
When the pointer is created, as I monitor memory at runtime, all elements have a default value of 0xCD, which is magenta on color chart. I use a for loop to populate the bytes I want with 0x00, but it will not write over the default array value of the third array.
So, I am stuck with my printer printing magenta instead of white space. Yet I can write over that array just fine with just the data. But not with the whitespace. Im unsure what is the reason for that. Can anyone give me any insight? Here is my code...
PrintLine(unsigned char* pbData, unsigned long ulDataSize, UINT xoffset)
{
if (xoffset > 0)
{ //create pointer to byte array for xoffset
unsigned char* offsetData;
offsetData = new unsigned char[(xoffset / 8)]; //x offset is divided by 8
//to convert pixels to bytes
//create pointer to byte array to hold image data and offset data
unsigned char* finalData;
finalData = new unsigned char[ulDataSize + (xoffset / 8)];
//begin final data with image data passed into the function
for (int count = 0; count < ulDataSize; count++)
{
finalData[count] = pbData[count];
}
//populate offset data with blank bytes
for (int count = 0; count < (xoffset / 8); count++)
{
offsetData[count] = 0x00;
}
//add blank data for offset to finalData
int position = 0;
for (int count = ulDataSize; count < ulDataSize + (xoffset / 8);count++)
{
finalData[ulDataSize] = offsetData[position];//also tried =0x00
position++;
}
//Send data to printer.
if (!(Write(finalData, ulDataSize + (xoffset / 8)))
{
return FALSE;
}
return TRUE;
}
}

Answer 1

At first glance your code don't have errors, but I see something that looks suspicious. I'm talking about the line:
finalData[ulDataSize] = offsetData[position]; //also tried =0x00
I think what you want is:
finalData[count] = offsetData[position];//also tried =0x00
On the other hand you could write your loop like this:
for (int count = 0; count < (xoffset / 8); count++)
{
finalData[ulDataSize + count] = offsetData[count];
}
Making the code much more readable.