Difference between revisions of "C programming/pointers"

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=Basic pointer=
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The following sourcecode demonstrates the basic pointer:
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<source lang=c>
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#include <stdio.h>
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int main( void ) {
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  int x = 100;
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  int *pointer;
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  pointer = &x;  // Set pointer to address of <x>
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  printf("Value of int <pointer> points to: %d\n", *pointer);
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  // Changing the value of the int <pointer> points to
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  *pointer = *pointer + 99;
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  printf("<pointer> value %d and <x> value %d\n", *pointer, x);
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  // Working the actual addresses
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  printf("The address contained in <pointer> %p\n", pointer);
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  printf("The address of <x> %p - Should be the same as the above address!\n", &x);
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  printf("The <pointer> has it's own address also, which is %p\n", &pointer);
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  return(0);
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}
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</source>
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=Review of C Pointer Declarations=
 
=Review of C Pointer Declarations=
 
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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