C / C++ / MFC

nahitan wrote:

the thing is that after a while the port number gets changed if there is no traffic

<br />
char* buffer = new char[settings.getAccessesToSimulate()];<br />
char* fname = settings.getFileName();<br />
<br />
ifstream binFile(fname, ios::in|ios::binary);<br />
<br />
if(!binFile)<br />
{<br />
   //handle error code<br />
}<br />
<br />
binFile.read(buffer,settings.getAccessesToSimulate());<br />
<br />
binFile.close();<br />
<br />

Mustafa Ismail Mustafa wrote:

After this little beauty runs, I get buffer = "gsA" which is incorrect since I'm giving it 1000 characters to read. Opening the file manually (in windows, not linux where its supposed to be) shows me that there's an NUL right after those three characters (they're actually hex).

48 65 6C 6C 6F 00 48 65 6C 6C 6F

int fd = open(fname, O_RDONLY);
const int nBytesRead = read(fd, buffer, 1000);
close(fd);

int fd = _open(fname, _O_RDONLY|_O_BINARY);
const int nBytesRead = _read(fd, buffer, 1000);
_close(fd);

binFile.read(buffer, 1000);
std::cout << binFile.gcount() << std::endl;

Mustafa Ismail Mustafa wrote:

After restarting the computer, things worked perfectly

Stuart Dootson wrote:

Don't you hate computers sometimes

Mustafa Ismail Mustafa wrote:

A different binary file, is being read and this time, I need to clump every 4 bytes into one structure and this structure would be a member in an array of its type. Suggestions?

1. Does the file have the same endian-ness as the computer you're working on?
2. Do you know how many elements the array has?
3. What format is the 'structure' you talk about?

• Interpreting the file byte-by-byte, to read into the structure
• Read the file a structure (four bytes at a time), assuming that the structure can be represented as four contiguous bytes in memory. I'd use #pragma pack to do that, with a static assert[^] to ensure that the structure really takes up four bytes in memory. If endian-ness is an issue, then you can reverse bytes at this point.
• Read the whole array in, if you know how many members it has. To ensure that padding doesn't get in the way, you could read in the correct number of bytes (sizeof structure * element_count), then use a byte pointer to step through the bytes, casting the pointer to a structure pointer when accessing the bytes