Dangling Pointer in C?

[arjunkumar]

Hello Everyone, I am preparing for my upcoming interview which is c language based. I want to know concept of dangling pointer in C? and In how many ways can a pointer act as a Dangling Pointer? When A pointer is pointing to a memory location, and a B pointer deletes the memory occupied by the A pointer, then the A pointer still points to the memory location? So Can anyone know about it and explains to me with some examples of dangling pointer.

[rohanjoshi0894]

Dangling pointers arise when an object is deleted or de-allocated, without modifying the value of the pointer, so that the pointer still points to the memory location of the de-allocated memory. In short pointer pointing to non-existing memory location is called dangling pointer. 

Example:

 

#include<stdlib.h>
{
    char *ptr = malloc(Constant_Value);
    .......
    .......
    .......
    free (ptr);      /* ptr now becomes a dangling pointer */
}

[teempade04]

Dangling Pointer occurs when a pointer pointing to a variable goes out of scope or when an object/variable's memory gets deallocated. Also, the occurrence of Dangling Pointers can result in some unexpected errors during the execution of a program, so we have to make sure to avoid them while writing a program.

mobdro
 

myfiosgateway.one
 

Edited February 9, 2023 by teempade04