Thread: '/0' in strings

Hi,

I wrote the following code:

Code:

#include <stdio.h>


int main(void)
{
    char str[100] = "Hello world";
    char *last;
    
    for(last = str; (*last) != '\0'; last++)
        ;
    
    last--;
    printf("last char: %c\n", *last);
    
    return 0;
}

Now I'm wondering why I need the statement last--; to get the last char. Shouldn't the for loop stop before reaching '\0'?
I was thinking the same program as above but leaving out the last--; would give us output: 'd'.

And what output does it produce without the last--?

Shouldn't the for loop stop before reaching '\0'?

No, it stops when it reaches the termination character.

Jim

Hi,
in C strings are 0-terminated, your statement

char str[100] = "Hello world";

automatically appends a (char) 0 ; so the last character of a string is followed by (char) 0.
Your for-loop moves pointer "last" forward until the address where it points to has a value of (char) 0, this is 1 byte further than the last character of your string.
last-- puts your char-pointer 1 byte back so that it points to the last character (one byte before the '\0'.

Ah ok, got it now, thanks!!