分段故障

Question

i want to find the Length of a String without Using strlen() function. but it gives me segmentation fault error.

#include <stdio.h>
#include <string.h>

unsigned string_length(char str[])
{
  int i;
  printf("Enter a string:");
  scanf("%s",&str);
  for (i = 0; str[i] != '\0';++i)
  {
  }
  printf("Length of string: %d", i);
  return i;
}
int main()
{
  int ausgabe;
  char str[100];
  ausgabe = string_length(str[100]);
  return 0;
}

This is what i did, i have tried with all possible variations (all i know (while, for, even with if)) but non of them seem to be the answer to my problem. I am new to programming and would welcome advice from professionals

Answer 1

Don't need to pass &str to scanf("%s",&str); only pass str (without reference operator) to scanf. Also, the better way to create a function is like following (see input parameters of string_length function):

#include <stdio.h>
#include <string.h>

unsigned string_length(char str[])
{
  int i;
  //printf("Enter a string:");
  //scanf("%s",&str);
  for (i = 0; str[i] != '\0';++i)
          ;
  //printf("Length of string: %d", i);
  return i;
}
int main()
{
  int ausgabe;
  char str[100];
  printf("%s", "Enter a string:");
  scanf("%s",str);
  ausgabe = string_length(str);
  printf("Length of string: %d\n", ausgabe);

  return 0;
}