« XPCOM API Reference


Reallocates a block of memory using the XPCOM memory manager.

#include "nsXPCOM.h"
void* NS_Realloc(
  void* aPtr,
  PRSize aSize


[in] A pointer to the block of memory to reallocate. This pointer must have been previously allocated by the XPCOM memory manager, or this parameter may be null in which case this function behaves like NS_Alloc.
[in] The size in bytes of the block to allocate, or zero if the given block is to be freed.

Return Values

This function returns a pointer to the allocated block of memory, which is suitably aligned for any kind of variable, or null if the allocation failed.


This function provides a convenient way to access the XPCOM memory manager. It is equivalent to calling realloc on the nsIMemory instance returned from NS_GetMemoryManager.


This function was finalized for Mozilla 1.8. See bug 267767 for details.

See Also

nsIMemory, NS_GetMemoryManager

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 Contributors to this page: Sheppy, DarinFisher, Nickolay
 Last updated by: Sheppy,