Simple Parameters in C

Example 1 - pass by value - in only type parameters

#include <stdio.h>

/** prototypes **/

int cube_it(int value);      /* int cube_it(int);   */


int main(void)
{
  int number = 3, cube;

  cube = cube_it(number);
  printf("\n%d cubed = %d\n", number, cube);

  return(0);
}


/** cube_it - brief description, etc. since this is the place for
*** for the function header when commenting your code.
**/

int cube_it(int value)            /* int cube_it(int value)            */
{                                 /* {                                 */ 
  int answer;                     /*    return(value * value * value); */
                                  /* }                                 */
  answer = value * value * value;
  return(answer);
}

Example 2 - Pass an address to simulate Ada's in out parameters

#include <stdio.h>

/* prototypes */

void changer(int *val);    /* void changer(int *); */

int main(void)
{
  int number = 3;

  printf("\nBefore changer number = %d\n", number);
  printf("\nAddress of number = %X\n", &number);
 
  changer(&number);

  printf("\nAfter changer number = %d\n", number);

  return (0);
}


/** header goes here **/

void changer(int *value)
{
  printf("\nIn changer value = %X", value);
  printf("\n *value = %d", *value);
 
  *value = 27;
}

Example 3 - Pass an address to simulate Ada's out only

#include <stdio.h>

/* prototypes */

void get_int(int *);

int main(void)
{
   int number;

   printf("\nEnter an integer ");
   get_int(&number);
   printf("\n number = %d\n", number);

   return (0);
}


void get_int(int *value)          /* void get_int(int *value)    */
{                                 /* {                           */
  int temp;                       /*    scanf("%d", value);      */
                                  /* }                           */
  scanf("%d", &temp);
  *value = temp;
}