Question

The following C code returns a “segmentation fault” error. I do not understand why it does not return the value 20. What is my error?

#include <stdio.h>

int main() 
{
    int* n;
    *n = 20;

    printf("%i\n",*n);

    return 0;

}

Answer 1

You haven’t allocated memory to n, so

*n = 20;

attempts to write unspecified memory.

Try

#include <stdlib.h>

int *n = malloc(sizeof *n);
/* use n */
free(n);