_heapchk

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Header File

malloc.h

Prototype

int _heapchk(void);

Description

Checks and verifies the heap.

_heapchk walks through the heap and examines each block, checking its pointers, size, and other critical attributes.

Return Value

One of the following values:

HEAPBADNODE	corrupted heap block has been found
HEAPEMPTY	No heap exists
_HEAPOK	The heap appears to be uncorrupted

Portability

	POSIX	ANSI C	ANSI C++	Win32	Win64	macOS
_heapchk				+

Example

#include <stdio.h>
#include <alloc.h>

#define NUM_PTRS  10
#define NUM_BYTES 16

int main(void) {
    char *array[NUM_PTRS];
    int i;

    for (i = 0; i < NUM_PTRS; i++)
        array[i] = (char *) malloc(NUM_BYTES);

    for (i = 0; i < NUM_PTRS; i += 2)
        free(array[i]);

    if (heapcheck() == _HEAPCORRUPT)
        printf("Heap is corrupted.\n");
    else
        printf("Heap is OK.\n");

    return 0;
}

See Also

• _heapset
• _rtl_heapwalk