Typedef quint16 on ARM and Win32

I am using qint type definitions in my applications, but I have a serius problems with the croosplatform compitability.

The structure that I use:

struct DatagramHeader
{
quint8 version;
quint16 lenght;
quint16 checkSum;
}

The problem is that sizeof(DatagramHeader) prints out different value (from Win32) when used on ARM.

Why???

Regards,
Samo

Probably the problem is not in qints, but in alignment. On normal 32-bit system that structure most likely will look like this:

Code:

---

| version |xxxxxxxxx|       length      |
|     checksum      |xxxxxxxxx|xxxxxxxxx|

---

but on x86 it can be also:

Code:

---

| version |       length      |     chec |
| ksum    |

---

If you rely on the order and position of structure elements, you should force compiler to pack the structure. If you use GCC, try:

Code:

---

struct DatagramHeader
{
   ...
} __attribute__ ((packed));

---

Thank you for fast reply....

I am using this structures to create a datagram header. I add it like this:

//Adding Header to the datagram
//Setting up variables
struct DatagramHeader header;
int size=sizeof(DatagramHeader);
//Preparing heder
QByteArray newDatagram = QByteArray::fromRawData((char *)&header, sizeof(DatagramHeader));
//Appending data
newDatagram.append(datapacket.data);

And reading from the datagram:
//Cheching the datagram
struct DatagramHeader* header;
header= (DatagramHeader*) datapacket.data.constData();

Is there a better way to do it?

Regards,
Samo

You might try the QDataStream class.