need help assigning one structure to another using pointers
Hi,
i have two pointer to structures named *currMB and *PrevMB and i want to assign PrevMB into currMB.
will the C++ code below work.
struct Macroblock *currMB;
struct Macroblock *PrevMB;
*currMB= & PrevMB;
and if i want to average these two structures and put the output in currMB.
then can i write
currMB = (currMB+PrevMB)/2;
This will probably be a compiler error, but if not you would be assigning the address of PrevMB to the content of currMB, which is not what you want.Originally Posted by naeem561
Both pointers will point to the same struct. If you want to copy the contents:Code:currMB = PrevMB;
Code:memcpy(currMB,PrevMB,sizeof(struct Macroblock));For sure not.then can i write
currMB = (currMB+PrevMB)/2;
C programming resources:
GNU C Function and Macro Index -- glibc reference manual
The C Book -- nice online learner guide
Current ISO draft standard
CCAN -- new CPAN like open source library repository
3 (different) GNU debugger tutorials: #1 -- #2 -- #3
cpwiki -- our wiki on sourceforge
*currMB is a struct, while &PrevMB is a pointer to a pointer to a struct, so they're not comparable at all.
(currMB+PrevMB)/2 is the average of the addresses stored in those variables (since that's what currMB and PrevMB are storing, addresses).
