Thread: Reversing a string declared as char[] works, but as char* it segfaults. Why?

Code:

#include <stdio.h>

void reverse(char* string, int length) {
    char otherString[length + 1];
    for (int i = 0; i < length; i++) {
        otherString[i] = string[length - i - 1];
    }
    otherString[length] = '\0';
    for (int i = 0; i < length; i++) {
        string[i] = otherString[i];
    }
}

int main() {
    //char* string = "ABCDE"; //this segfaults. Why?
    char string[] = "ABCDE";
    printf("Before: %s\n", string);
    reverse(string, 5);
    printf("After: %s\n", string);
    return 0;
}

Besides the, most certainly, not very performant string reversal function, I'm confused with the differences between passing a string param to reverse it. If I declare it as string[], it works just fine. But if I declared it as char*, it segfaults. Why is it?

I welcome any resource that might document this further.