If you have pointer ptr;
MyClass *ptr;
Then the size of that pointer is
sizeof ptr
or
sizeof(MyClass*).
Unfortunatelly, there is no portable way to get the size of allocated memory block at which ptr points.
Main Topics
Browse All TopicsIs there any way to know that whether a pointer has been allocated or not ? What is the memory size allocated to a pointer ?
Thks so much.
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The answer to your question depends on the type of data the pointer references. If the pointer is to a buffer, it's pretty much impossible to figure out how much memory is allocated,which is why many Windows API calls require that you pass not only a pointer to a buffer, but the size of the buffer.
What exactly are you trying to do?
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by: AlexFMPosted on 2006-11-14 at 06:30:56ID: 17938287
Int 32-bits OS this is 4 bytes, in 64-bits OS this is 8 bytes. Pointer has always size which is enough to cover whole address space.
To know whether pointer is allocated or not, always initialize it to 0. When pointer is released, reset it to 0 again.