# pragma pack (1)//turn off struct packing for this struct.
struct TEST
{
WORD Size; //2 bytes
WORD ID; //2 byte
char text[10]; //10 bytes
}UNALIGNED test2;
# pragma pack ()//turn it back to normal
Creating a struct, typecast to char* and pull out elements of the struct
Author
Basically what im trying to do (and please shoot me if this is really bad) is I have a struct with no alignment I am creating
I'm not sure if this is the most proper way of doing this, but you should be able to get it by dereferencing your pointer
WORD* SizePtr = (WORD*)test2;
WORD* IDPtr = (WORD*)( test2 + sizeof(WORD) );
WORD Size = *SizePtr;
WORD ID = *IDPtr
[Edited by - Riraito on January 20, 2009 8:43:02 PM]
WORD* SizePtr = (WORD*)test2;
WORD* IDPtr = (WORD*)( test2 + sizeof(WORD) );
WORD Size = *SizePtr;
WORD ID = *IDPtr
[Edited by - Riraito on January 20, 2009 8:43:02 PM]
Quote:Original post by smitty1276
What's wrong with just casting it to the struct type?
I assume he wants to determine which type to cast it to by looking at the size and ID fields. In which case the usual solution is to send a separate "Header" struct (or even just an enum) beforehand with that information. The receiver casts to the Header type, then determines what type the next received object will be based on the ID. You must ensure that you always send a Header before a Message.
Quote:Original post by scjohnnoYeah, or you just inherit all of your datatypes from a PacketBase type that has that info in it.Quote:Original post by smitty1276
What's wrong with just casting it to the struct type?
I assume he wants to determine which type to cast it to by looking at the size and ID fields. In which case the usual solution is to send a separate "Header" struct (or even just an enum) beforehand with that information. The receiver casts to the Header type, then determines what type the next received object will be based on the ID. You must ensure that you always send a Header before a Message.
struct PacketBase{ int packetType; int packetSize;};struct AwesomePacket : public PacketBase{ int awesomeData;};This topic is closed to new replies.
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