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Changes the size of a memory block that was allocated with _aligned_malloc or _aligned_offset_malloc.

void * _aligned_realloc(
   void *memblock, 
   size_t size, 
   size_t alignment


The current memory block pointer.
The size of the requested memory allocation.
The alignment value, which must be an integer power of 2.

Return Value

_aligned_realloc returns a void pointer to the reallocated (and possibly moved) memory block. The return value is NULL if the size is zero and the buffer argument is not NULL, or if there is not enough available memory to expand the block to the given size. In the first case, the original block is freed. In the second, the original block is unchanged. The return value points to a storage space that is guaranteed to be suitably aligned for storage of any type of object. To get a pointer to a type other than void, use a type cast on the return value.

It is an error to reallocate memory and change the alignment of a block.


_aligned_realloc is based on malloc; see malloc for more information on using _aligned_offset_malloc.


Routine Required header Compatibility
_aligned_realloc <malloc.h> Win 98, Win Me, Win NT, Win 2000, Win XP

For additional compatibility information, see Compatibility in the Introduction.


All versions of the C run-time libraries.


See _aligned_malloc for a sample that uses _aligned_realloc.

See Also

Data Alignment | Run-Time Routines and .NET Framework Equivalents