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 36 37 38 39 40 41 42 43 44 45 46 | #include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <assert.h>
#include <string.h>
/*
∙ &▒ means address of ▒
∙ *▒ means value at ▒ (which should be an address)
∙ *▒ = ░ means store ░ at ▒ (▒ should be an address)
∙ When you declare a variable like this…
▒▒▒* ░ = …
The type of the variable will be "address of a ▒▒▒".
∙ One way to print an address from your program is to use
printf("%p", (void*) ▒);
∙ The (void*) typecasts ▒ to an address of anything.
*/
int main(int argc, char* argv[]) {
int n = 5;
int* a_n = &n;
printf("Address of n is %p.\n", (void*) a_n);
printf("Value at %p is %d\n", (void*) a_n, *a_n);
// *a_n = 7;
// What would happen if we didn't use the *?
a_n = 7;
printf("Value at %p is %d\n", (void*) a_n, *a_n);
/*
c.c: In function ‘main’:
c.c:32:6: warning: assignment to ‘int *’ from ‘int’ makes pointer from integer without a cast [-Wint-conversion]
a_n = 7;
^
*/
return EXIT_SUCCESS;
}
/* vim: set tabstop=4 shiftwidth=4 fileencoding=utf-8 noexpandtab: */
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