Difference between revisions of "C programming/pointers"
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printf("Value of int <pointer> points to: %d\n", *pointer); | printf("Value of int <pointer> points to: %d\n", *pointer); | ||
+ | |||
+ | // Changing the value of the int <pointer> points to | ||
+ | *pointer = *pointer + 99; | ||
+ | printf("<pointer> value %d and <x> value %d\n", *pointer, x); | ||
+ | |||
+ | // Working the actual addresses | ||
printf("The address contained in <pointer> %p\n", pointer); | printf("The address contained in <pointer> %p\n", pointer); | ||
printf("The address of <x> %p - Should be the same as the above address!\n", &x); | printf("The address of <x> %p - Should be the same as the above address!\n", &x); | ||
Line 16: | Line 22: | ||
return(0); | return(0); | ||
} | } | ||
+ | </source> | ||
=Review of C Pointer Declarations= | =Review of C Pointer Declarations= |
Latest revision as of 12:15, 26 May 2015
Basic pointer
The following sourcecode demonstrates the basic pointer:
#include <stdio.h>
int main( void ) {
int x = 100;
int *pointer;
pointer = &x; // Set pointer to address of <x>
printf("Value of int <pointer> points to: %d\n", *pointer);
// Changing the value of the int <pointer> points to
*pointer = *pointer + 99;
printf("<pointer> value %d and <x> value %d\n", *pointer, x);
// Working the actual addresses
printf("The address contained in <pointer> %p\n", pointer);
printf("The address of <x> %p - Should be the same as the above address!\n", &x);
printf("The <pointer> has it's own address also, which is %p\n", &pointer);
return(0);
}
Review of C Pointer Declarations
int *p | p is a pointer to int |
int *p[13] | p is an array[13] of pointer to int |
int *(p[13]) | p is an array[13] of pointer to int |
int **p | p is a pointer to a pointer to an int |
int (*p)[13] | p is a pointer to an array[13] of int |
int *f() | f is a function returning a pointer to int |
int (*f)() | f is a pointer to a function returning int |
int (*(*f())[13])() | f is a function returning ptr to an array[13] of pointers to functions returning int |
int (*(*x[3])())[5] | x is an array[3] of pointers to functions returning pointers to array[5] of ints |