c - Copying object via pointer and address -


let's have pointer structure, tm:

time_t timestamp = time(null); tm* = localtime(&timestamp);

to create pointer copy in automatic memory, copy value can used:

tm copy = *now; tm* next = © // next points copy in memory

but why shortcut doesn't copy value new memory block? (gcc compiler)

tm* next = &(*now); // next points address of

this may sound trivial i'm not sure mechanism behind. why there difference?

= copying data 1 memory location another. & gives address of variable. * dereferences variable. none of these allocate memory in form, or create temporary variables.

all memory allocations must explicitly stated in c. there no difference found here.


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