Re: Check that a buffer has been completely written
* Paolo:
I have to create an application that receive some packet from an
interface and builds a file from those. In the header there are three
fields: one is the total lenght of the file, one is the offset of the
packet in the file and one is the lenght of the current packet.
I made a function that gets all the packets and reconstruct the file.
while(...)
{
FilePart part;
......
char* fileBuffer = new char[fileLenght];
int offset = part->offset;
int lenght = part->lenght;
memmove(fileBuffer + offset, part->buffer, lenght);
lenghtCheck += lenght;
}
'int' may not have the range required to represent a file size.
I used lenghtCheck to check that the sum of all the lenghts is the
same as the original file. If this is true, I then write the file.
(I didn't post a complete code since this seems to work)
My problem is that the file isn't the same as the original opnbe, some
parts are missing. I though that maybe I overwrite some parts of the
buffer (maybe some offsets are wrong?).
I'd like a function to check that every byte of the fileBuffer array
has been overwritten. DO you know how I can do this?
For example, use a std::bitset where each bit represents one byte.
Update the bitset as you write. Check it at the end.
The file is binary, not text.
Irrelevant.
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