I'm trying to malloc some memory for a struct pointer. The code compiles fine, but when I run it I get bus error: 10 after the user enters their name. I'm not sure what I'm doing wrong so would appreciate any help!
Thanks in advance:)
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
int main(){
struct name{
char *first;
char *last;
};
struct name *user;
char temp[10];
printf("What is your first name?\n");
scanf("%s", temp);
user->first = (char*) malloc(strlen(temp)+1);
strcpy(user->first, temp);
printf("What is your last name?\n");
scanf("%s", temp);
user->last = (char*) malloc(strlen(temp)+1);
strcpy(user->last, temp);
printf("Your name is %s %s\n", user->first, user->last);
free(user->first);
free(user->last);
user->first = NULL;
user->last = NULL;
}
You didn't allocate memory for user
to point to. So it is left uninitialized and attempting to dereference that pointer leads to undefined behavior .
You need to allocate memory for user
, just as you did for its fields:
struct name *user = malloc(sizeof *user);
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