1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <assert.h>

int main(int argc, char* argv[]) {
    char* s = "abc";  // We think of s as a "string" but s is actually the address of the
                      // first character in that string.
                      // REMINDER:  The string at s is read-only.
    
    printf("s    == \"%s\"\n", s);   // Type of s is char*.

    printf("s[0] == '%c'\n", s[0]);  // Type of s[0] is char.
    printf("*s   == '%c'\n", *s);    // Type of *s is char.
    // If s is a char*, then *s is a char.
    // *s is equivalent to s[0]
    // If s is a char*, then s[0] is a char.

    printf("s[1] == '%c'\n", s[1]);            // Type of s[1] is char.
    printf("*(s + 1) == '%c'\n", *(s + 1));    // Type of *(s + 1) is char.
    // s[♣] is equivalent to *(s + ♣).
    // s[1] is equivalent to *(s + 1).
    // *(s + 1) is a char.

    printf("s[2] == '%c'\n", s[2]);            // Type of s[1] is char.
    printf("*(s + 2) == '%c'\n", *(s + 2));    // Type of *(s + 1) is char.


    // REMINDER:  You cannot write to a string on the data segment (read-only portion).
    // When you initialize a char* with a string literal ("…"), that will be the address
    // of a string on the data segment (read-only portion).

    return EXIT_SUCCESS;
}
/* vim: set tabstop=4 shiftwidth=4 fileencoding=utf-8 noexpandtab: */

© Copyright 2023 Alexander J. Quinn         This content is protected and may not be shared, uploaded, or distributed.