Structure pointer returning the start byte of memb

Question

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• Crash or “segmentation fault” when data is copied/scanned/read to an uninitialized pointer 5 answers

Structure pointer returning the start byte of member of structure .I wondered how it works. PLease some one help me to get know about this.

 #include <stdio.h>

 typedef struct node {
  char mem;
  double mem2;
  char mem3;
  int mem4;
  char mem5;
  char mem6;
 }NODE;
 int main()
 {
     NODE * m;
     printf("%u",&m->mem3);
     return 0;
 }

Output is 16

Answer 1

The program actually should crash because pointer m is not pointing valid memory location. Below code can give the result.

NODE M;
NODE *ptr = &m;
Printf(“%x”, &ptr->mem3);

%x will give hexadecimal address value.