realloc
- Updated2023-02-21
- 1 minute(s) read
realloc
void *realloc (void *memBlockPointer, size_t newSize);
Purpose
Changes the size of a memory block that has been previously allocated while preserving the contents. If the new size is larger, the value of the newly allocated portion of the object is indeterminate. If the space cannot be allocated, the memory block remains unchanged.
Parameters
| Input | ||
| Name | Type | Description |
| memBlockPointer | void * | Contains a pointer to the memory block whose allocated space is altered. If this parameter contains a null pointer, this function behaves like malloc. If the pointer does not match one obtained earlier by calloc, malloc, or this function, the behavior is undefined. |
| newSize | size_t | Specifies the new size for the memory block. If the new size is larger, the value of the newly allocated portion of the memory block is indeterminate. If the new size is smaller, the contents at the end of the block are lost accordingly. If the size is zero and if memBlockPointer is not a null pointer, the object it points to is freed. |
Return Value
| Name | Type | Description |
| newMemBlockPointer | void * | Contains a pointer to the possibly moved allocated space. If the space cannot be allocated or if the size of the space requested is zero, the function returns a null pointer. |
Additional Information
Library: ANSI C Library
Include file: ansi_c.h
LabWindows/CVI compatibility: LabWindows/CVI 3.0 and later
Example
Refer to userint\ICOViewer.cws for an example of using the realloc function.