Memory Allocation
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The latest version of this topic can be found at Memory Allocation.
Use these routines to allocate, free, and reallocate memory.
Memory-Allocation Routines
| Routine | Use | .NET Framework equivalent |
|---|---|---|
| _alloca, _malloca | Allocate memory from stack | Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples. |
| calloc | Allocate storage for array, initializing every byte in allocated block to 0 | Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples. |
| _calloc_dbg | Debug version of calloc; only available in the debug versions of the run-time libraries |
Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples. |
| operator delete | Free allocated block | Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples. |
| operator delete[] | Free allocated block | Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples. |
| _expand | Expand or shrink block of memory without moving it | Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples. |
| _expand_dbg | Debug version of _expand; only available in the debug versions of the run-time libraries |
Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples. |
| free | Free allocated block | Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples. |
| _free_dbg | Debug version of free; only available in the debug versions of the run-time libraries |
Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples. |
| _freea | Free allocated block from stack | Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples. |
| _get_heap_handle | Get Win32 HANDLE of the CRT heap. | Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples. |
| _heapadd | Add memory to heap | Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples. |
| _heapchk | Check heap for consistency | Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples. |
| _heapmin | Release unused memory in heap | Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples. |
| _heapset | Fill free heap entries with specified value | Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples. |
| _heapwalk | Return information about each entry in heap | Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples. |
| malloc | Allocate block of memory from heap | Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples. |
| _malloc_dbg | Debug version of malloc; only available in the debug versions of the run-time libraries |
Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples. |
| _msize | Return size of allocated block | Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples. |
| _msize_dbg | Debug version of _msize; only available in the debug versions of the run-time libraries |
Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples. |
| new | Allocate block of memory from heap | Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples. |
| new[] | Allocate block of memory from heap | Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples. |
| _query_new_handler | Return address of current new handler routine as set by _set_new_handler |
Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples. |
| _query_new_mode | Return integer indicating new handler mode set by _set_new_mode for malloc |
Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples. |
| realloc | Reallocate block to new size | Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples. |
| _realloc_dbg | Debug version of realloc; only available in the debug versions of the run-time libraries |
Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples. |
| _set_new_handler | Enable error-handling mechanism when new operator fails (to allocate memory) and enable compilation of Standard Template Libraries (STL) |
Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples. |
| _set_new_mode | Set new handler mode for malloc |
Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples. |